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Fair Value Measurements (Details 2) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
ASSETS |  |  |  |
Held to Maturity, Fair Value, Total |  | $ 1,383,621 | $ 1,417,608 |
Federal Home Loan Bank Stock |  | 46,304 | 43,557 |
Bank Owned Life Insurance |  | 298,352 | 297,387 |
LIABILITIES |  |  |  |
Federal Home Loan Bank borrowings (f) |  | 962,535 | 1,105,541 |
Subordinated Debt |  |  | 49,980 |
Deposits [Member] |  |  |  |
LIABILITIES |  |  |  |
Time certificates of deposits (f) | [1] | 12,610,236 | 12,684,068 |
Accrued Liabilities, Fair Value Disclosure | [1] | 12,610,236 | 12,684,068 |
Time certificates of deposits (f) |  |  |  |
LIABILITIES |  |  |  |
Time certificates of deposits (f) | [2] | 2,432,985 | 2,181,479 |
Accrued Liabilities, Fair Value Disclosure | [2] | 2,418,961 | 2,166,573 |
Federal Home Loan Bank borrowings (f) |  |  |  |
LIABILITIES |  |  |  |
Federal Home Loan Bank borrowings (f) | [2] | 962,535 | 1,105,541 |
Federal Home Loan Bank Borrowings, Fair Value Disclosure | [2] | 960,942 | 1,103,845 |
Junior subordinated debentures (g) |  |  |  |
LIABILITIES |  |  |  |
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust | [3] | 62,858 | 62,858 |
Accrued Liabilities, Fair Value Disclosure | [3] | 59,740 | 58,911 |
Subordinated debentures (f) |  |  |  |
LIABILITIES |  |  |  |
Subordinated Debt | [2] |  | 49,980 |
Accrued Liabilities, Fair Value Disclosure | [2] |  | 49,613 |
Significant Other Observable Inputs (Level 2) | Deposits [Member] |  |  |  |
LIABILITIES |  |  |  |
Accrued Liabilities, Fair Value Disclosure | [1] | 12,610,236 | 12,684,068 |
Significant Other Observable Inputs (Level 2) | Time certificates of deposits (f) |  |  |  |
LIABILITIES |  |  |  |
Accrued Liabilities, Fair Value Disclosure | [2] | 2,418,961 | 2,166,573 |
Significant Other Observable Inputs (Level 2) | Federal Home Loan Bank borrowings (f) |  |  |  |
LIABILITIES |  |  |  |
Federal Home Loan Bank Borrowings, Fair Value Disclosure | [2] | 960,942 | 1,103,845 |
Significant Other Observable Inputs (Level 2) | Junior subordinated debentures (g) |  |  |  |
LIABILITIES |  |  |  |
Accrued Liabilities, Fair Value Disclosure | [3] | 59,740 | 58,911 |
Significant Unobservable Inputs (Level 3) | Subordinated debentures (f) |  |  |  |
LIABILITIES |  |  |  |
Accrued Liabilities, Fair Value Disclosure | [2] |  | 49,613 |
U.S. Government agency securities |  |  |  |
ASSETS |  |  |  |
Debt Securities, Held-to-maturity |  | 29,086 | 29,521 | [4]
Held to Maturity, Fair Value, Total |  | 28,243 | 28,408 | [4]
U.S. Government agency securities | Significant Other Observable Inputs (Level 2) |  |  |  |
ASSETS |  |  |  |
Held to Maturity, Fair Value, Total |  | 28,243 | 28,408 | [4]
U.S. treasury securities |  |  |  |
ASSETS |  |  |  |
Debt Securities, Held-to-maturity | [4] | 100,732 | 100,712 |
Held to Maturity, Fair Value, Total | [4] | 90,810 | 91,535 |
U.S. treasury securities | Significant Other Observable Inputs (Level 2) |  |  |  |
ASSETS |  |  |  |
Held to Maturity, Fair Value, Total | [4] | 90,810 | 91,535 |
Agency mortgage-backed securities |  |  |  |
ASSETS |  |  |  |
Debt Securities, Held-to-maturity | [4] | 819,912 | 829,431 |
Held to Maturity, Fair Value, Total | [4] | 748,601 | 763,728 |
Agency mortgage-backed securities | Significant Other Observable Inputs (Level 2) |  |  |  |
ASSETS |  |  |  |
Held to Maturity, Fair Value, Total | [4] | 748,601 | 763,728 |
Agency collateralized mortgage obligations |  |  |  |
ASSETS |  |  |  |
Debt Securities, Held-to-maturity | [4] | 465,016 | 477,517 |
Held to Maturity, Fair Value, Total | [4] | 393,258 | 407,911 |
Agency collateralized mortgage obligations | Significant Other Observable Inputs (Level 2) |  |  |  |
ASSETS |  |  |  |
Held to Maturity, Fair Value, Total | [4] | 393,258 | 407,911 |
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] | 1,372 | 1,373 |
Single issuer trust preferred securities issued by banks | Significant Other Observable Inputs (Level 2) |  |  |  |
ASSETS |  |  |  |
Held to Maturity, Fair Value, Total | [4] | 1,372 | 1,373 |
Small Business Administration Pooled Securities [Member] |  |  |  |
ASSETS |  |  |  |
Debt Securities, Held-to-maturity | [4] | 129,021 | 130,426 |
Held to Maturity, Fair Value, Total | [4] | 121,337 | 124,653 |
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] | 121,337 | 124,653 |
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] | 14,154,357 | 14,106,967 |
Loans Receivable, Fair Value Disclosure | [5] | 13,074,151 | 13,079,368 |
Loans, net of allowance for credit losses (b) | Significant Unobservable Inputs (Level 3) |  |  |  |
ASSETS |  |  |  |
Loans Receivable, Fair Value Disclosure | [5] | 13,074,151 | 13,079,368 |
Investment in Federal Home Loan Bank Stock [Member] |  |  |  |
ASSETS |  |  |  |
Federal Home Loan Bank Stock | [6] | 46,304 | 43,557 |
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | [6] | 46,304 | 43,557 |
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] | 46,304 | 43,557 |
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] | 298,352 | 297,387 |
Bank Owned Life Insurance | [7] | 298,352 | 297,387 |
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] | 298,352 | 297,387 |
Cash Surrender Value [Member] | Significant Unobservable Inputs (Level 3) |  |  |  |
ASSETS |  |  |  |
Cash Surrender Value, Fair Value Disclosure | [7] | $ 0 | $ 0 |
[1] | Fair value of demand deposits, savings and interest checking accounts and money market deposits is the amount payable on demand at the reporting date.
[2] | Fair value was determined by discounting anticipated future cash payments using rates currently available for instruments with similar remaining maturities.
[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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