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Fair Value Measurements (Details 3) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
ASSETS |  |  |
Debt Securities, Held-to-maturity |  | $ 777,798 | $ 740,806
Held to Maturity, Fair Value, Total |  | 809,355 | 753,263
Loans, net of allowance for credit losses(b) |  | 8,824,054 | 8,805,899
Federal Home Loan Bank Stock |  | 23,274 | 14,424
Bank Owned Life Insurance |  | 197,772 | 197,372
LIABILITIES |  |  |
Federal Home Loan Bank borrowings(f) |  | 358,591 | 115,748
Long-term Debt | [1] | 74,920 | 74,906
Long-term Debt, Fair Value | [1] | 73,572 | 72,219
Subordinated Debt |  | 49,625 | 49,601
Deposits [Member] |  |  |
LIABILITIES |  |  |
Time certificates of deposits(f) | [2] | 8,146,490 | 7,752,052
Accrued Liabilities, Fair Value Disclosure | [2] | 8,146,490 | 7,752,052
Time certificates of deposits(f) |  |  |
LIABILITIES |  |  |
Time certificates of deposits(f) | [1] | 1,269,708 | 1,395,315
Accrued Liabilities, Fair Value Disclosure | [1] | 1,279,983 | 1,396,760
Federal Home Loan Bank borrowings(f) |  |  |
LIABILITIES |  |  |
Federal Home Loan Bank borrowings(f) | [1] | 358,591 | 115,748
Federal Home Loan Bank Borrowings, Fair Value Disclosure | [1] | 359,249 | 115,881
Junior subordinated debentures(g) |  |  |
LIABILITIES |  |  |
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust | [3] | 62,849 | 62,848
Accrued Liabilities, Fair Value Disclosure | [3] | 61,528 | 65,603
Subordinated debentures(f) |  |  |
LIABILITIES |  |  |
Subordinated Debt | [1] | 49,625 | 49,601
Accrued Liabilities, Fair Value Disclosure | [1] | 51,896 | 52,870
Quoted Prices in Active Markets for Identical Assets (Level 1) | Long-term Debt [Member] |  |  |
LIABILITIES |  |  |
Long-term Debt, Fair Value | [1] | 0 | 0
Significant Other Observable Inputs (Level 2) | Deposits [Member] |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [2] | 8,146,490 | 7,752,052
Significant Other Observable Inputs (Level 2) | Time certificates of deposits(f) |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [1] | 1,279,983 | 1,396,760
Significant Other Observable Inputs (Level 2) | Federal Home Loan Bank borrowings(f) |  |  |
LIABILITIES |  |  |
Federal Home Loan Bank Borrowings, Fair Value Disclosure | [1] | 359,249 |
Accrued Liabilities, Fair Value Disclosure | [1] |  | 115,881
Significant Other Observable Inputs (Level 2) | Long-term Debt [Member] |  |  |
LIABILITIES |  |  |
Long-term Debt, Fair Value | [1] | 73,572 | 72,219
Significant Other Observable Inputs (Level 2) | Junior subordinated debentures(g) |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [3] | 61,528 | 65,603
Significant Unobservable Inputs (Level 3) | Long-term Debt [Member] |  |  |
LIABILITIES |  |  |
Long-term Debt, Fair Value | [1] | 0 | 0
Significant Unobservable Inputs (Level 3) | Subordinated debentures(f) |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [1] | 51,896 | 52,870
U.S. Government agency securities |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] |  | 12,874
Held to Maturity, Fair Value, Total | [4] |  | 12,997
U.S. Government agency securities | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] |  | 12,997
U.S. Treasury securities |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] | 4,029 | 4,032
Held to Maturity, Fair Value, Total | [4] | 4,139 | 4,053
U.S. Treasury securities | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 4,139 | 4,053
Agency mortgage-backed securities |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] | 463,632 | 397,414
Held to Maturity, Fair Value, Total | [4] | 482,363 | 405,802
Agency mortgage-backed securities | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 482,363 | 405,802
Agency collateralized mortgage obligations |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] | 277,921 | 293,662
Held to Maturity, Fair Value, Total | [4] | 289,902 | 297,314
Agency collateralized mortgage obligations | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 289,902 | 297,314
Single issuer trust preferred securities issued by banks |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] | 1,500 | 1,500
Held to Maturity, Fair Value, Total | [4] | 1,490 | 1,490
Single issuer trust preferred securities issued by banks | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 1,490 | 1,490
Small Business Administration Pooled Securities [Member] |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] | 30,716 | 31,324
Held to Maturity, Fair Value, Total | [4] | 31,461 | 31,607
Small Business Administration Pooled Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 0 | 0
Small Business Administration Pooled Securities [Member] | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 31,461 | 31,607
Small Business Administration Pooled Securities [Member] | Significant Unobservable Inputs (Level 3) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 0 | 0
Loans, net of allowance for credit losses(b) |  |  |
ASSETS |  |  |
Loans, net of allowance for credit losses(b) | [5] | 8,784,610 | 8,780,384
Loans Receivable, Fair Value Disclosure | [5] | 8,626,697 | 8,613,635
Loans, net of allowance for credit losses(b) | Significant Unobservable Inputs (Level 3) |  |  |
ASSETS |  |  |
Loans Receivable, Fair Value Disclosure | [5] | 8,626,697 | 8,613,635
Investment in Federal Home Loan Bank Stock [Member] |  |  |
ASSETS |  |  |
Federal Home Loan Bank Stock | [6] | 23,274 | 14,424
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | [6] | 23,274 | 14,424
Investment in Federal Home Loan Bank Stock [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
ASSETS |  |  |
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | [6] | 0 | 0
Investment in Federal Home Loan Bank Stock [Member] | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | [6] | 23,274 | 14,424
Investment in Federal Home Loan Bank Stock [Member] | Significant Unobservable Inputs (Level 3) |  |  |
ASSETS |  |  |
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | [6] | 0 | 0
Cash Surrender Value [Member] |  |  |
ASSETS |  |  |
Cash Surrender Value, Fair Value Disclosure | [7] | 197,772 | 197,372
Bank Owned Life Insurance | [7] | 197,772 | 197,372
Cash Surrender Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
ASSETS |  |  |
Cash Surrender Value, Fair Value Disclosure | [7] | 0 | 0
Cash Surrender Value [Member] | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Cash Surrender Value, Fair Value Disclosure | [7] | 197,772 | 197,372
Cash Surrender Value [Member] | Significant Unobservable Inputs (Level 3) |  |  |
ASSETS |  |  |
Cash Surrender Value, Fair Value Disclosure | [7] | $ 0 | $ 0
[1] | Fair value was determined by discounting anticipated future cash payments using rates currently available for instruments with similar remaining maturities.
[2] | Fair value of demand deposits, savings and interest checking accounts and money market deposits is the amount payable on demand at the reporting date.
[3] | Fair value was determined based upon market prices of securities with similar terms and maturities.
[4] | The fair values presented are based on quoted market prices, where available. If quoted market prices are not available, fair values are based on quoted market prices of comparable instruments and/or discounted cash flow analysis.
[5] | Fair value of loans is measured using the exit price valuation method, determined primarily by discounting the future cash flows using the current rates at which similar loans would be made to borrowers with similar credit ratings and for the same remaining maturities or cash flows, while incorporating liquidity and credit assumptions. Additionally, this amount excludes collateral dependent impaired loans, which are deemed to be marked to fair value on a nonrecurring basis.
[6] | FHLB stock has no quoted market value and is carried at cost, therefore the carrying amount approximates fair value.
[7] | Cash surrender value of life insurance is recorded at its cash surrender value (or the amount that can be realized upon surrender of the policy), therefore carrying amount approximates fair value.

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