Slicers (applies to each fact value in each table cell)

Reporting Entity [Axis]

0001479750 (http://www.sec.gov/CIK)

Fair Value Disclosures [Abstract]	Period [Axis]
	2016-01-01 - 2016-12-31
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on a Recurring Basis	Assets and liabilities measured at fair value on a recurring basis as of December 31, 2016 are summarized below: (Dollars in thousands)       Fair Value Measurement Using:     Total   Quoted Prices in Active Markets for Identical Assets (Level 1)   Significant Other Observable Inputs (Level 2)   Significant Unobservable Inputs (Level 3) Assets                 Trading securities   $ 3,791   $ —   $ 3,791   $ — Available-for-sale securities:                 Mortgage-backed securities—residential   868,922   —   868,922   — State and political subdivisions - tax exempt   11,077   —   11,077   — Industrial revenue bonds   3,298   —   —   3,298 Corporate bonds   28,953   —   28,953   — Available-for-sale securities   $ 912,250   $ —   $ 908,952   $ 3,298 Gross asset value of derivatives   $ 1,078   $ —   $ 1,078   $ — Liabilities                 Gross liability value of derivatives   $ 1,354   $ —   $ 1,354   $ — There were no transfers of assets and liabilities between levels of the fair value hierarchy during the year ended December 31, 2016. Assets and liabilities measured at fair value on a recurring basis as of December 31, 2015 are summarized below: (Dollars in thousands)       Fair Value Measurement Using:     Total   Quoted Prices in Active Markets for Identical Assets (Level 1)   Significant Other Observable Inputs (Level 2)   Significant Unobservable Inputs (Level 3) Assets                 Trading securities   $ 3,013   $ —   $ 3,013   $ — Available-for-sale securities:                 Mortgage-backed securities—residential   611,137   —   611,137   — Industrial revenue bonds   3,437   —   —   3,437 Corporate bonds   22,755   —   22,755   — Available-for-sale securities   $ 637,329   $ —   $ 633,892   $ 3,437 Gross asset value of derivatives   $ 933   $ —   $ 933   $ — Liabilities                 Gross liability value of derivatives   $ 110   $ —   $ 110   $ —
Fair Value Measurements on Recurring Basis Using Significant Unobservable Inputs (Level 3)	The tables below present the activity and income statement classifications of gains and losses for all assets measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the year ended and held at December 31, 2016: (Dollars in thousands)     Fair Value Measurement Using Significant Unobservable Inputs (Level 3)       Industrial Revenue Bonds Beginning balance, January 1, 2016     $ 3,437 Principal reduction     (170 ) Included in other comprehensive income     31 Ending balance, December 31, 2016     $ 3,298 The tables below present the activity and income statement classifications of gains and losses for all assets measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the year ended and held at December 31, 2015: (Dollars in thousands)   Fair Value Measurement Using Significant Unobservable Inputs (Level 3)     Industrial Revenue Bonds Beginning balance, January 1, 2015   $ 3,690 Principal reduction   (170 ) Included in other comprehensive income   (83 ) Ending balance, December 31, 2015   $ 3,437
Quantitative Information About Recurring Level 3 Fair Value Measurements	(Dollars in thousands)   Fair Value at December 31, 2016   Valuation Technique   Significant Unobservable Input   Range Industrial revenue bonds   $ 3,298   Discounted cash flow   Discount rate   3.31% - 3.35%             Illiquidity factor   0.5% (Dollars in thousands)   Fair Value at December 31, 2015   Valuation Technique   Significant Unobservable Input   Range Industrial revenue bonds   $ 3,437   Discounted cash flow   Discount rate   3.75% - 3.78%             Illiquidity factor   0.5%
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis	Assets and liabilities measured at fair value on a nonrecurring basis as of December 31, 2016 are summarized below: (Dollars in thousands)   Fair Value Measurement Using:     Quoted Prices in Active Markets for Identical Assets (Level 1)   Significant Other Observable Inputs (Level 2)   Significant Unobservable Inputs (Level 3) Assets             Other real estate owned   $ —   $ —   $ 41,168 Other repossessed assets   163   —   — Impaired loans   —   —   1,420 Other real estate owned measured at fair value as of December 31, 2016 had a gross amount of $50.0 million, less valuation allowances totaling $8.9 million and is made up of $35.5 million commercial properties and $5.7 million residential properties. Other repossessed assets are primarily comprised of repossessed vehicles and equipment and are measured at fair value as of the date of repossession. Assets and liabilities measured at fair value on a nonrecurring basis as of December 31, 2015 are summarized below: (Dollars in thousands)   Fair Value Measurement Using:     Quoted Prices in Active Markets for Identical Assets (Level 1)   Significant Other Observable Inputs (Level 2)   Significant Unobservable Inputs (Level 3) Assets             Other real estate owned   $ —   $ —   $ 34,645 Other repossessed assets   —   375   — Impaired loans   —   —   254
Quantitative Information About Nonrecurring Level 3 Fair Value Measurements	(Dollars in thousands)   Fair Value at December 31, 2016   Valuation Technique   Significant Unobservable Input   Weighted Average Other real estate owned   $ 41,168   Fair value of property   Appraised value less cost to sell   7.91% Impaired loans   1,420   Fair value of collateral   Appraised value less cost to sell   7.47% (Dollars in thousands)   Fair Value at December 31, 2015   Valuation Technique   Significant Unobservable Input   Weighted Average Other real estate owned   $ 34,645   Fair value of property   Appraised value less cost to sell   7.86% Impaired loans   254   Fair value of collateral   Appraised value less cost to sell   7.29%
Carrying Amounts and Estimated Fair Values of Financial Instruments	Carrying amount and estimated fair values of financial instruments were as follows: (Dollars in thousands)   Fair Value Measurement December 31, 2016   Carrying Value   Estimated Fair Value   Level 1   Level 2   Level 3 Financial Assets                     Cash and cash equivalents   $ 309,055   $ 309,055   $ 309,055   $ —   $ — Trading securities   3,791   3,791   —   3,791   — Investment securities available-for-sale   912,250   912,250   —   908,952   3,298 Investment securities held-to-maturity   463,959   460,911   —   460,911   — Loans, net   7,363,127   7,395,128   —   12,874   7,382,254 Other earning assets (1)   32,050   32,050   —   —   32,050 Gross asset value of derivatives   1,078   1,078   —   1,078   — Total financial assets   $ 9,085,310   $ 9,114,263   $ 309,055   $ 1,387,606   $ 7,417,602 Financial Liabilities                     Non-contractual deposits   $ 5,743,316   $ 5,743,316   $ —   $ 5,743,316   $ — Contractual deposits   2,137,312   2,121,519   —   2,121,519   — Federal Home Loan Bank advances   545,701   546,023   —   546,023   — Short-term borrowings   19,157   19,154   —   19,154   — Subordinated debentures   116,456   114,593   —   —   114,593 Gross liability value of derivatives   1,354   1,354   —   1,354   — Total financial liabilities   $ 8,563,296   $ 8,545,959   $ —   $ 8,431,366   $ 114,593 (1) Includes Federal Home Loan Bank stock. (Dollars in thousands)   Fair Value Measurement December 31, 2015   Carrying Value   Estimated Fair Value   Level 1   Level 2   Level 3 Financial Assets                     Cash and cash equivalents   $ 144,696   $ 144,696   $ 144,696   $ —   $ — Trading securities   3,013   3,013   —   3,013   — Investment securities available-for-sale   637,329   637,329   —   633,892   3,437 Investment securities held-to-maturity   472,505   475,134   —   475,134   — Loans, net   5,587,682   5,636,518   —   10,569   5,625,949 FDIC indemnification asset   6,725   6,725   —   —   6,725 Receivable from FDIC   678   678   —   678   — Other earning assets (1)   25,736   25,736   —   —   25,736 Gross asset value of derivatives   933   933   —   933   — Total financial assets   $ 6,879,297   $ 6,930,762   $ 144,696   $ 1,124,219   $ 5,661,847 Financial Liabilities                     Non-contractual deposits   $ 4,112,892   $ 4,112,892   $ —   $ 4,112,892   $ — Contractual deposits   1,747,318   1,735,587   —   1,735,587   — Federal Home Loan Bank advances   460,898   461,128   —   461,128   — Short-term borrowings   12,410   12,410   —   12,410   — Subordinated debentures   85,777   92,517   —   —   92,517 Gross liability value of derivatives   110   110   —   110   — Total financial liabilities   $ 6,419,405   $ 6,414,644   $ —   $ 6,322,127   $ 92,517    (1) Includes Federal Home Loan Bank stock.