| Pension and Other Postretirement Benefit Expense [Abstract] | Period [Axis] |
|---|
2016-01-01 - 2016-12-31 |
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Pension and Other Postretirement Benefit Expense [Abstract] | |
Schedule Of Allocation of Plan Assets | Asset Mix Policy of Funds: | | | | | | | | | | Defined Benefit Pension Plan | | Postretirement Benefit Plan | Asset Category | Minimum | | Maximum | | Minimum | | Maximum | Domestic Equities | 35% | | 55% | | 35% | | 55% | International Equities | 10% | | 20% | | 15% | | 25% | Fixed Income | 30% | | 50% | | 20% | | 50% | Short-Term Investments | 0% | | 10% | | 0% | | 10% |
Pension Plan and Postretirement Plan Asset Mix at December 31, 2016 and December 31, 2015: | | | | | | | | | | | | | | | December 31, 2016 | Defined Benefit
Pension Plan Assets | | Postretirement
Benefit Plan Assets | Asset Class | Asset Value | | % of Total Assets | | Asset Value | | % of Total Assets | | (in millions) | | | | (in millions) | | | Domestic Equities | $ | 148.7 |
| | 42.7 | % | | $ | 95.9 |
| | 41.5 | % | International Equities | 56.3 |
| | 16.2 | % | | 43.4 |
| | 18.8 | % | Fixed Income | 136.3 |
| | 39.2 | % | | 76.9 |
| | 33.2 | % | Cash/Other | 6.8 |
| | 1.9 | % | | 15.1 |
| | 6.5 | % | Total | $ | 348.1 |
| | 100.0 | % | | $ | 231.3 |
| | 100.0 | % | | | | | | | | | December 31, 2015 | Defined Benefit
Pension Plan Assets | | Postretirement
Benefit Plan Assets | Asset Class | Asset Value | | % of Total Assets | | Asset Value | | % of Total Assets | | (in millions) | | | | (in millions) | | | Domestic Equities | $ | 141.0 |
| | 39.4 | % | | $ | 101.6 |
| | 44.4 | % | International Equities | 62.5 |
| | 17.5 | % | | 42.8 |
| | 18.8 | % | Fixed Income | 123.3 |
| | 34.4 | % | | 76.6 |
| | 33.6 | % | Cash/Other | 31.0 |
| | 8.7 | % | | 7.2 |
| | 3.2 | % | Total | $ | 357.8 |
| | 100.0 | % | | $ | 228.2 |
| | 100.0 | % |
|
Schedule Of Fair Value and Changes In The Fair Value Of The Plan Assets | | | | | | | | | | | | | | | | | | Fair Value Measurements (in millions) | December 31,
2016 | | Quoted Prices in Active
Markets for Identical Assets (Level 1) | | Significant Other
Observable Inputs (Level 2) | | Significant
Unobservable Inputs (Level 3) | Pension plan assets | | | | | | | | Cash | $ | 0.2 |
| | $ | 0.2 |
| | $ | — |
| | $ | — |
| Fixed income securities | | | | | | | | Government | 8.8 |
| | — |
| | 8.8 |
| | — |
| Corporate | 19.5 |
| | — |
| | 19.5 |
| | — |
| Commingled funds | | | | | | | | Short-term money markets(2) | 6.6 |
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|
| |
|
| |
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| U.S. equities(2) | 93.1 |
| |
|
| |
|
| |
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| International equities(2) | 56.3 |
| |
|
| |
|
| |
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| Fixed income(2) | 73.2 |
| |
| |
|
| |
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| Mutual funds | | | | | | | | U.S. equities | 55.6 |
| | 55.6 |
| | — |
| | — |
| Fixed income | 34.8 |
| | 34.8 |
| | — |
| | — |
| Pension plan assets subtotal | 348.1 |
| | 90.6 |
| | 28.3 |
| | — |
| Other postretirement benefit plan assets | | | | | | | | Cash | 0.4 |
| | 0.4 |
| | — |
| | — |
| Commingled funds | | | | | | | | Short-term money markets(2) | 14.7 |
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|
| |
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| |
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| U.S. equities(2) | 1.0 |
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|
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|
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| Mutual funds | | | | | | | | U.S. equities | 94.9 |
| | 94.9 |
| | — |
| | — |
| International equities | 43.4 |
| | 43.4 |
| | — |
| | — |
| Fixed income | 76.9 |
| | 76.9 |
| | — |
| | — |
| Other postretirement benefit plan assets subtotal | 231.3 |
| | 215.6 |
| | — |
| | — |
| Due to brokers, net(1) | (0.2 | ) | | | | | | | Accrued investment income/dividends | 0.6 |
| | | | | | | Total pension and other postretirement benefit plan assets | $ | 579.8 |
| | $ | 306.2 |
| | $ | 28.3 |
| | $ | — |
|
(1)This class represents pending trades with brokers. (2)This class of investments is measured at fair value using the net asset value per share and has not been classified in the fair value hierarchy. The table below sets forth a summary of unfunded commitments, redemption frequency and redemption notice periods for certain investments that are measured at fair value using the net asset value per share for the year ended December 31, 2016: | | | | | | | | | | | | | (in millions) | Fair Value | | Unfunded Commitments | | Redemption Frequency | | Redemption Notice Period | Commingled Funds | | | | | | | | Short-term money markets | $ | 21.3 |
| | $ | — |
| | Daily | | 1 day | U.S. equities | 94.1 |
| | — |
| | Daily | | 1 day | International equities | 56.3 |
| | — |
| | Daily | | 2 days | Fixed income | 73.2 |
| | — |
| | Daily | | 2-3 days | Total | $ | 244.9 |
| | — |
| | | | |
Fair Value Measurements at December 31, 2015: | | | | | | | | | | | | | | | | | Fair Value Measurements (in millions) | December 31,
2015 | | Quoted Prices in Active
Markets for Identical Assets (Level 1) | | Significant Other
Observable Inputs (Level 2) | | Significant
Unobservable Inputs (Level 3) | Pension plan assets | | | | | | | | Cash | $ | 0.9 |
| | $ | 0.9 |
| | $ | — |
| | $ | — |
| Equity securities | | | | | | | | International equities | 6.6 |
| | 6.6 |
| | — |
| | — |
| Fixed income securities | | | | | | | | Government | 8.5 |
| | — |
| | 8.5 |
| | — |
| Corporate | 13.0 |
| | — |
| | 13.0 |
| | — |
| Commingled funds | | | | | | | | Short-term money markets(2) | 31.1 |
| |
|
| |
|
| |
|
| U.S. equities(2) | 141.0 |
| |
|
| |
|
| |
|
| International equities(2) | 55.6 |
| |
|
| |
|
| |
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| Fixed income(2) | 100.9 |
| |
|
| |
|
| |
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| Pension plan assets subtotal | 357.6 |
| | 7.5 |
| | 21.5 |
| | — |
| Other postretirement benefit plan assets | | | | | | | | Commingled funds | | | | | | | | Short-term money markets(2) | 7.3 |
| |
|
| |
|
| |
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| U.S. equities(2) | 13.9 |
| |
|
| |
|
| |
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| Mutual funds | | | | | | | | U.S. equities | 87.7 |
| | 87.7 |
| | — |
| | — |
| International equities | 42.8 |
| | 42.8 |
| | — |
| | — |
| Fixed income | 76.5 |
| | 76.5 |
| | — |
| | — |
| Other postretirement benefit plan assets subtotal | 228.2 |
| | 207.0 |
| | — |
| | — |
| Due to brokers, net(1) | (0.4 | ) | | | | | | | Accrued investment income/dividends | 0.6 |
| | | | | | | Total pension and other postretirement benefit plan assets | $ | 586.0 |
| | $ | 214.5 |
| | $ | 21.5 |
| | $ | — |
|
(1)This class represents pending trades with brokers. (2)This class of investments is measured at fair value using the net asset value per share and has not been classified in the fair value hierarchy. The table below sets forth a summary of changes in the fair value of the Plan’s Level 3 assets for the year ended December 31, 2015: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | (in millions) | Balance at January 1, 2015 | | Total gains or losses (unrealized / realized) | | Purchases | | (Sales) | | Transfers into/(out of) level 3 | | Separation Allocation(1) | | Balance at December 31, 2015 | Fixed income securities | | | | | | | | | | | | | | Other fixed income | $ | 0.1 |
| | $ | — |
| | $ | — |
| | $ | — |
| | $ | — |
| | $ | (0.1 | ) | | $ | — |
| Private equity limited partnerships | | | | | | | | | | | | | | U.S. multi-strategy | 8.5 |
| | — |
| | — |
| | — |
| | — |
| | (8.5 | ) | | — |
| International multi-strategy | 5.3 |
| | — |
| | — |
| | — |
| | — |
| | (5.3 | ) | | — |
| Distressed opportunities | 1.1 |
| | — |
| | — |
| | — |
| | — |
| | (1.1 | ) | | — |
| Real estate | 2.6 |
| | — |
| | — |
| | — |
| | — |
| | (2.6 | ) | | — |
| Total | $ | 17.6 |
| | $ | — |
| | $ | — |
| | $ | — |
| | $ | — |
| | $ | (17.6 | ) | | $ | — |
|
(1)Level 3 assets were not contributed to the CPG Plans upon Separation from NiSource and no subsequent investments were made in Level 3 assets post Separation. The table below sets forth a summary of unfunded commitments, redemption frequency and redemption notice periods for certain investments that are measured at fair value using the net asset value per share for the year ended December 31, 2015: | | | | | | | | | | | | | (in millions) | Fair Value | | Unfunded Commitments | | Redemption Frequency | | Redemption Notice Period | Commingled Funds | | | | | | | | Short-term money markets | $ | 38.4 |
| | $ | — |
| | Daily | | 1 day | U.S. equities | 154.9 |
| | — |
| | Monthly | | 3 days | International equities | 55.6 |
| | — |
| | Monthly | | 14-30 days | Fixed income | 100.9 |
| | — |
| | Monthly | | 3 days | Total | $ | 349.8 |
| | $ | — |
| | | | |
|
Schedule Of Reconciliation Of The Plan Funded Status | | | | | | | | | | | | | | | | | | | Pension Benefits | | Other Postretirement Benefits | (in millions) | 2016 | | 2015 | | 2016 | | 2015 | Change in projected benefit obligation(1) | | | | | | | | Benefit obligation at beginning of year | $ | 404.5 |
| | $ | 397.6 |
| | $ | 112.1 |
| | $ | 124.2 |
| Service cost | 6.4 |
| | 5.9 |
| | 0.9 |
| | 1.0 |
| Interest cost | 15.1 |
| | 15.0 |
| | 4.5 |
| | 4.7 |
| Plan participants’ contributions | — |
| | — |
| | 2.8 |
| | 2.3 |
| Actuarial (gain) loss | (4.7 | ) | | (6.9 | ) | | 2.1 |
| | (12.4 | ) | Settlement loss | 3.2 |
| | — |
| | — |
| | — |
| Benefits paid | (48.8 | ) | | (29.7 | ) | | (13.6 | ) | | (9.8 | ) | Estimated benefits paid by incurred subsidy | — |
| | — |
| | 0.3 |
| | 0.3 |
| Transfer of participant balances from NiSource plans(2) | — |
| | 22.6 |
| | — |
| | 1.8 |
| Projected benefit obligation at end of year | $ | 375.7 |
| | $ | 404.5 |
| | $ | 109.1 |
| | $ | 112.1 |
| Change in plan assets | | | | | | | | Fair value of plan assets at beginning of year | $ | 357.8 |
| | $ | 351.0 |
| | $ | 228.2 |
| | $ | 223.8 |
| Actual return on plan assets | 30.7 |
| | 1.2 |
| | 13.6 |
| | (2.5 | ) | Employer contributions | 8.4 |
| | 20.0 |
| | 0.3 |
| | 13.5 |
| Plan participants’ contributions | — |
| | — |
| | 2.8 |
| | 2.3 |
| Benefits paid | (48.8 | ) | | (29.7 | ) | | (13.6 | ) | | (9.8 | ) | Transfer of participant balances from NiSource plans(2) | — |
| | 15.3 |
| | — |
| | 0.9 |
| Fair value of plan assets at end of year | $ | 348.1 |
| | $ | 357.8 |
| | $ | 231.3 |
| | $ | 228.2 |
| Funded status at end of year | $ | (27.6 | ) | | $ | (46.7 | ) | | $ | 122.2 |
|
| $ | 116.1 |
| Amounts recognized in the balance sheet consist of: | | | | | | | | Noncurrent assets | $ | — |
| | $ | — |
| | $ | 122.2 |
| | $ | 116.1 |
| Current liabilities | — |
| | (0.8 | ) | | — |
| | — |
| Noncurrent liabilities | (27.6 | ) | | (45.9 | ) | | — |
| | — |
| Net amount recognized at end of year(3) | $ | (27.6 | ) | | $ | (46.7 | ) | | $ | 122.2 |
| | $ | 116.1 |
| Amounts recognized in AOCI or regulatory assets/liabilities(4) | | | | | | | | Unrecognized prior service credit | $ | (2.6 | ) | | $ | (3.7 | ) | | $ | (1.3 | ) | | $ | (2.0 | ) | Unrecognized actuarial loss (gain) | 133.0 |
| | 164.5 |
| | (0.7 | ) | | (3.9 | ) | Total recognized AOCI or regulatory assets/liabilities | $ | 130.4 |
| | $ | 160.8 |
| | $ | (2.0 | ) | | $ | (5.9 | ) |
(1)The change in benefit obligation for Pension Benefits represents the change in Projected Benefit Obligation while the change in benefit obligation for Other Postretirement Benefits represents the change in Accumulated Postretirement Benefit Obligation. (2)Reflects the transfer of additional pension and OPEB plan participants to CPGSC upon Separation from NiSource that were determined in the current year. (3)CPG recognizes in its Consolidated Balance Sheets the underfunded and overfunded status of its various defined benefit postretirement plans, measured as the difference between the fair value of the plan assets and the benefit obligation. (4)CPG determined that the future recovery of pension and other postretirement benefits costs is probable. CPG recorded regulatory assets and liabilities of $111.3 million and zero, respectively, as of December 31, 2016, and $135.2 million and $0.7 million, respectively, as of December 31, 2015 that would otherwise have been recorded to accumulated other comprehensive loss. |
Schedule Of Significant Actuarial Assumptions In Determining Funded Status Plan | | | | | | | | | | | | | | | Pension Benefits | | Other Postretirement Benefits | | 2016 | | 2015 | | 2016 | | 2015 | Weighted-average assumptions to Determine Benefit Obligation | | | | | | | | Discount Rate | 4.10 | % | | 4.05 | % | | 4.25 | % | | 4.29 | % | Rate of Compensation Increases | 2.50 | % | | 4.00 | % | | | | | Health Care Trend Rates | | | | | | | | Trend for Next Year | | | | | 8.47 | % | | 8.39 | % | Ultimate Trend | | | | | 4.50 | % | | 4.50 | % | Year Ultimate Trend Reached | | | | | 2024 |
| | 2022 |
|
|
Schedule Of One-Percentage-Point Change In Assumed Health Care Cost Trend Rates | | | | | | | | | | (in millions) | 1% point increase | | 1% point decrease | Effect on service and interest components of net periodic cost | $ | 0.1 |
| | $ | (0.1 | ) | Effect on accumulated postretirement benefit obligation | 2.6 |
| | (2.4 | ) |
|
Schedule Of Expected Payments To Participants In Pension Plan | | | | | | | | | | | | | | (in millions) | Pension Benefits | | Other
Postretirement Benefits | | Federal
Subsidy Receipts | Year(s) | | | | | | 2017 | $ | 32.3 |
| | $ | 7.8 |
| | $ | 0.5 |
| 2018 | 33.1 |
| | 7.8 |
| | 0.5 |
| 2019 | 33.8 |
| | 7.8 |
| | 0.4 |
| 2020 | 35.2 |
| | 7.7 |
| | 0.4 |
| 2021 | 34.9 |
| | 7.6 |
| | 0.4 |
| 2022-2026 | 168.8 |
| | 35.5 |
| | 1.2 |
|
|
Components Of The Plans' Net Periodic Benefits Cost | | | | | | | | | | | | | | | | | | | | | | | | | | | Pension Benefits | | Other Postretirement Benefits | (in millions) | 2016 | | 2015 | | 2014 | | 2016 | | 2015 | | 2014 | Components of Net Periodic Benefit Cost (Income) | | | | | | | | | | | | Service cost | $ | 6.4 |
| | $ | 5.9 |
| | $ | 4.8 |
| | $ | 0.9 |
| | $ | 1.0 |
| | $ | 1.1 |
| Interest cost | 15.1 |
| | 15.0 |
| | 15.7 |
| | 4.5 |
| | 4.7 |
| | 4.6 |
| Expected return on assets | (25.0 | ) | | (28.2 | ) | | (27.3 | ) | | (15.0 | ) | | (18.1 | ) | | (16.6 | ) | Amortization of prior service (credit) cost | (1.2 | ) | | (1.1 | ) | | (1.1 | ) | | (0.7 | ) | | (0.3 | ) | | 0.1 |
| Recognized actuarial loss (gain) | 12.2 |
| | 9.9 |
| | 7.5 |
| | 0.3 |
| | (0.3 | ) | | — |
| Net Periodic Benefit Cost (Income) | 7.5 |
| | 1.5 |
| | (0.4 | ) | | (10.0 | ) | | (13.0 | ) | | (10.8 | ) | Additional loss recognized due to: | | | | | | | | | | | | Settlement loss | 12.3 |
| | — |
| | — |
| | — |
| | — |
| | — |
| Total Net Periodic Benefit Cost (Income) | $ | 19.8 |
| | $ | 1.5 |
| | $ | (0.4 | ) | | $ | (10.0 | ) | | $ | (13.0 | ) | | $ | (10.8 | ) |
|
Schedule Of Key Assumptions That Were Used To Calculate The Net Periodic Benefits Cost | | | | | | | | | | | | | | | | | | | | | Pension Benefits | | Other Postretirement Benefits | | 2016 | | 2015 | | 2014 | | 2016 | | 2015 | | 2014 | Weighted-average Assumptions to Determine Net Periodic Benefit Cost | | | | | | | | | | | | Discount Rate | 3.90 | % | | 3.84 | % | | 4.34 | % | | 4.12 | % | | 4.10 | % | | 4.76 | % | Expected Long-Term Rate of Return on Plan Assets | 7.29 | % | | 8.20 | % | | 8.30 | % | | 6.81 | % | | 8.05 | % | | 8.14 | % | Rate of Compensation Increases | 4.00 | % | | 4.00 | % | | 4.00 | % | | | | | | |
|
Schedule Of Changes In Plan Assets And Projected Benefit Obligations Recognized In Other Comprehensive Income | | | | | | | | | | | | | | | | | | | Pension Benefits | | Other Postretirement Benefits | (in millions) | 2016 | | 2015 | | 2016 | | 2015 | Other changes in plan assets and projected benefit obligations recognized in other comprehensive income or regulatory assets or liabilities | | | | | | | | Settlements | $ | (12.3 | ) | | $ | — |
| | $ | — |
| | $ | — |
| Net actuarial (gain) loss | (7.1 | ) | | 25.6 |
| | 3.5 |
| | 8.6 |
| Less: amortization of prior service cost | 1.2 |
| | 1.1 |
| | 0.7 |
| | 0.3 |
| Less: amortization of net actuarial (gain) loss | (12.2 | ) | | (9.9 | ) | | (0.3 | ) | | 0.3 |
| Total recognized in other comprehensive income or regulatory assets or liabilities | $ | (30.4 | ) | | $ | 16.8 |
| | $ | 3.9 |
| | $ | 9.2 |
| Amount recognized in net periodic benefit cost and other comprehensive income or regulatory assets or liabilities | $ | (10.6 | ) | | $ | 18.3 |
| | $ | (6.1 | ) | | $ | (3.8 | ) |
|