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Fair Value Measurements (Details 2) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
ASSETS |  |  |
Debt Securities, Held-to-maturity |  | $ 861,821 | $ 724,512
Held to Maturity, Fair Value, Total |  | 877,801 | 752,177
Loans, net of allowance for credit losses (b) |  | 8,836,631 | 9,279,474
Federal Home Loan Bank Stock |  | 9,079 | 10,250
Bank Owned Life Insurance |  | 242,963 | 200,525
LIABILITIES |  |  |
Federal Home Loan Bank borrowings (f) |  | 35,693 | 35,740
Long-term Debt | [1] | 23,425 | 32,773
Long-term Debt, Fair Value | [1] | 23,095 | 32,033
Subordinated Debt |  | 49,743 | 49,696
Deposits [Member] |  |  |
LIABILITIES |  |  |
Time certificates of deposits (f) | [2] | 11,169,652 | 10,042,541
Accrued Liabilities, Fair Value Disclosure | [2] | 11,169,652 | 10,042,541
Time certificates of deposits (f) |  |  |
LIABILITIES |  |  |
Time certificates of deposits (f) | [1] | 817,319 | 950,629
Accrued Liabilities, Fair Value Disclosure | [1] | 819,067 | 955,598
Federal Home Loan Bank borrowings (f) |  |  |
LIABILITIES |  |  |
Federal Home Loan Bank borrowings (f) | [1] | 35,693 | 35,740
Federal Home Loan Bank Borrowings, Fair Value Disclosure | [1] | 35,723 | 35,885
Junior subordinated debentures (g) |  |  |
LIABILITIES |  |  |
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust | [3] | 62,852 | 62,851
Accrued Liabilities, Fair Value Disclosure | [3] | 68,545 | 70,238
Subordinated debentures (f) |  |  |
LIABILITIES |  |  |
Subordinated Debt | [1] | 49,743 | 49,696
Accrued Liabilities, Fair Value Disclosure | [1] | 47,146 | 46,486
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] | 11,169,652 | 10,042,541
Significant Other Observable Inputs (Level 2) | Time certificates of deposits (f) |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [1] | 819,067 | 955,598
Significant Other Observable Inputs (Level 2) | Federal Home Loan Bank borrowings (f) |  |  |
LIABILITIES |  |  |
Federal Home Loan Bank Borrowings, Fair Value Disclosure | [1] | 35,723 | 35,885
Significant Other Observable Inputs (Level 2) | Long-term Debt [Member] |  |  |
LIABILITIES |  |  |
Long-term Debt, Fair Value | [1] | 23,095 | 32,033
Significant Other Observable Inputs (Level 2) | Junior subordinated debentures (g) |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [3] | 68,545 | 70,238
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] | 47,146 | 46,486
U.S. Government agency securities |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity |  | 33,853 |
Held to Maturity, Fair Value, Total |  | 33,730 |
U.S. Government agency securities | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total |  | 33,730 |
U.S. treasury securities |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] | 3,010 | 4,017
Held to Maturity, Fair Value, Total | [4] | 3,038 | 4,077
U.S. treasury securities | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 3,038 | 4,077
Agency mortgage-backed securities |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] | 381,030 | 356,085
Held to Maturity, Fair Value, Total | [4] | 392,042 | 374,121
Agency mortgage-backed securities | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 392,042 | 374,121
Agency collateralized mortgage obligations |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] | 418,112 | 335,993
Held to Maturity, Fair Value, Total | [4] | 421,841 | 344,119
Agency collateralized mortgage obligations | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 421,841 | 344,119
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] | 1,508 | 1,498
Single issuer trust preferred securities issued by banks | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [4] | 1,508 | 1,498
Small Business Administration Pooled Securities [Member] |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [4] | 24,316 | 26,917
Held to Maturity, Fair Value, Total | [4] | 25,642 | 28,362
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] | 25,642 | 28,362
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] | 8,806,355 | 9,247,964
Loans Receivable, Fair Value Disclosure | [5] | 8,782,780 | 9,253,381
Loans, net of allowance for credit losses (b) | Significant Unobservable Inputs (Level 3) |  |  |
ASSETS |  |  |
Loans Receivable, Fair Value Disclosure | [5] | 8,782,780 | 9,253,381
Investment in Federal Home Loan Bank Stock [Member] |  |  |
ASSETS |  |  |
Federal Home Loan Bank Stock | [6] | 9,079 | 10,250
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | [6] | 9,079 | 10,250
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] | 9,079 | 10,250
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] | 242,963 | 200,525
Bank Owned Life Insurance | [7] | 242,963 | 200,525
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] | 242,963 | 200,525
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 individually assessed collateral dependent loans, which are deemed to be marked to fair value on a nonrecurring basis.
[6] | Federal Home Loan Bank 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 policies 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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