| Compensation and Retirement Disclosure [Abstract] | Period [Axis] |
|---|
2016-01-01 - 2016-12-31 |
|---|
Compensation and Retirement Disclosure [Abstract] | |
Schedule of defined benefit plan activity | Obligations and Funded Status | | | | | | | | | | Years Ended December 31, | | 2016 | | 2015 | | (In Thousands) | Change in benefit obligation: | | | | Benefit obligation, January 1 | $ | 329,736 |
| | $ | 370,572 |
| Service cost | 3,784 |
| | 4,754 |
| Interest cost | 11,668 |
| | 14,459 |
| Actuarial (gain) loss | 8,374 |
| | (28,846 | ) | Benefits paid | (13,371 | ) | | (31,203 | ) | Benefit obligation, December 31 | 340,191 |
| | 329,736 |
| Change in plan assets: | | | | Fair value of plan assets, January 1 | 338,266 |
| | 373,062 |
| Actual return on plan assets | 11,732 |
| | (3,593 | ) | Benefits paid | (13,371 | ) | | (31,203 | ) | Fair value of plan assets, December 31 | 336,627 |
| | 338,266 |
| | | | | Funded status | (3,565 | ) | | 8,530 |
| Net actuarial loss | 37,445 |
| | 30,357 |
| Net amount recognized | $ | 33,880 |
| | $ | 38,887 |
|
|
Schedule of amounts recognized in balance sheet | Amounts recognized on the Company’s Consolidated Balance Sheets consist of: | | | | | | | | | | December 31, | | 2016 | | 2015 | | (In Thousands) | Prepaid benefit cost - other assets | $ | — |
| | $ | 8,530 |
| Accrued expenses and other liabilities | (3,565 | ) | | — |
| Deferred tax – other assets | 13,907 |
| | 11,235 |
| Accumulated other comprehensive loss | 23,538 |
| | 19,122 |
| Net amount recognized | $ | 33,880 |
| | $ | 38,887 |
|
|
Schedule of amounts recognized in income statements | The components of net periodic benefit cost recognized in the Company’s Consolidated Statements of Income are as follows. | | | | | | | | | | | | | | Years Ended December 31, | | 2016 | | 2015 | | 2014 | | (In Thousands) | Service cost | $ | 3,784 |
| | $ | 4,754 |
| | $ | 5,227 |
| Interest cost | 11,668 |
| | 14,459 |
| | 14,941 |
| Expected return on plan assets | (10,446 | ) | | (10,537 | ) | | (11,961 | ) | Recognized actuarial loss | — |
| | 563 |
| | 1,802 |
| Net periodic benefit cost | $ | 5,006 |
| | $ | 9,239 |
| | $ | 10,009 |
|
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Schedule of assumptions used in the defined benefit plan | The following table provides additional information related to the Company’s defined benefit pension plan. | | | | | | | | | | Years Ended December 31, | | 2016 | | 2015 | | (Dollars in Thousands) | Change in defined benefit plan included in other comprehensive income | $ | 4,416 |
| | $ | (9,706 | ) | | | | | Weighted average assumptions used to determine benefit obligation at December 31: | | | | Discount rate | 4.04 | % | | 4.30 | % | Rate of compensation increase | 3.00 | % | | 3.00 | % | | | | | Weighted average assumptions used to determine net pension income for year ended December 31: | | | | Discount rate - benefit obligations | 4.29 | % | | 3.97 | % | Discount rate - service cost | 4.52 | % | | 3.97 | % | Discount rate - interest cost | 3.62 | % | | 3.97 | % | Expected return on plan assets | 3.15 | % | | 2.87 | % | Rate of compensation increase | 3.00 | % | | 3.25 | % |
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Schedule of assumptions used in the defined benefit plan | The following table provides additional information related to the Company’s defined benefit pension plan. | | | | | | | | | | Years Ended December 31, | | 2016 | | 2015 | | (Dollars in Thousands) | Change in defined benefit plan included in other comprehensive income | $ | 4,416 |
| | $ | (9,706 | ) | | | | | Weighted average assumptions used to determine benefit obligation at December 31: | | | | Discount rate | 4.04 | % | | 4.30 | % | Rate of compensation increase | 3.00 | % | | 3.00 | % | | | | | Weighted average assumptions used to determine net pension income for year ended December 31: | | | | Discount rate - benefit obligations | 4.29 | % | | 3.97 | % | Discount rate - service cost | 4.52 | % | | 3.97 | % | Discount rate - interest cost | 3.62 | % | | 3.97 | % | Expected return on plan assets | 3.15 | % | | 2.87 | % | Rate of compensation increase | 3.00 | % | | 3.25 | % |
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Schedule of estimated benefit payments | The following table summarizes the estimated benefits to be paid in the following periods. | | | | | | (In Thousands) |
| 2017 | $ | 13,888 |
| 2018 | 14,751 |
| 2019 | 15,349 |
| 2020 | 16,216 |
| 2021 | 17,026 |
| 2022-2026 | 96,227 |
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Schedule of changes in fair value of benefit plans | The following table presents the fair value of the Company’s defined benefit pension plan assets. | | | | | | | | | | | | | | | | | | | | Quoted Prices in Active Markets for Identical Assets | | Significant Other Observable Inputs | | Significant Unobservable Inputs | | Fair Value | | (Level 1) | | (Level 2) | | (Level 3) | | (In Thousands) | December 31, 2016 | | Assets: | | Cash and cash equivalents | $ | 12,463 |
| | $ | 12,463 |
| | $ | — |
| | $ | — |
| Fixed income securities: | | | | | | | | U.S. Treasury and other U.S government agencies | 221,242 |
| | 200,391 |
| | 20,851 |
| | — |
| States and political subdivisions | 6,771 |
| | — |
| | 6,771 |
| | — |
| Corporate bonds | 96,151 |
| | — |
| | 96,151 |
| | — |
| Total fixed income securities | 324,164 |
| | 200,391 |
| | 123,773 |
| | — |
| Fair value of plan assets | $ | 336,627 |
| | $ | 212,854 |
| | $ | 123,773 |
| | $ | — |
| | | | | | | | | December 31, 2015 | | Assets: | | Cash and cash equivalents | $ | 5,167 |
| | $ | 5,167 |
| | $ | — |
| | $ | — |
| Fixed income securities: | | | | | | | | U.S. Treasury and other U.S. government agencies | 223,197 |
| | 203,050 |
| | 20,147 |
| | — |
| States and political subdivisions | 6,818 |
| | — |
| | 6,818 |
| | — |
| Corporate bonds | 103,084 |
| | — |
| | 103,084 |
| | — |
| Total fixed income securities | 333,099 |
| | 203,050 |
| | 130,049 |
| | — |
| Fair value of plan assets | $ | 338,266 |
| | $ | 208,217 |
| | $ | 130,049 |
| | $ | — |
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