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Fair Value Measurements (Details 2) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
ASSETS |  |  |
Held to Maturity, Fair Value, Total |  | $ 1,260,752 | $ 1,291,801
Federal Home Loan Bank Stock |  | 21,835 | 31,573
Bank Owned Life Insurance |  | 376,163 | 303,965
LIABILITIES |  |  |
Federal Home Loan Bank and other borrowings (f) |  | 416,240 | 638,514
Subordinated Debt |  | 296,275 | 0
Reported Value Measurement |  |  |
ASSETS |  |  |
Loans Receivable, Fair Value Disclosure | [1] | 18,219,929 | 14,294,628
Estimate of Fair Value Measurement |  |  |
ASSETS |  |  |
Loans Receivable, Fair Value Disclosure | [1] | 17,551,952 | 13,213,596
Deposits [Member] |  |  |
LIABILITIES |  |  |
Time certificates of deposits (f) | [2] | 16,875,881 | 12,558,632
Accrued Liabilities, Fair Value Disclosure | [2] | 16,875,881 | 12,558,632
Time certificates of deposits (f) |  |  |
LIABILITIES |  |  |
Time certificates of deposits (f) | [3] | 3,419,988 | 2,747,346
Accrued Liabilities, Fair Value Disclosure | [3] | 3,414,295 | 2,739,606
Federal Home Loan Bank and other borrowings (f) |  |  |
LIABILITIES |  |  |
Federal Home Loan Bank and other borrowings (f) | [3] | 416,240 | 638,514
Federal Home Loan Bank Borrowings, Fair Value Disclosure | [3] | 404,268 | 638,489
Junior subordinated debentures (g) |  |  |
LIABILITIES |  |  |
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust | [4] | 62,862 | 62,860
Accrued Liabilities, Fair Value Disclosure | [4] | 62,416 | 61,661
Subordinated debentures (f) |  |  |
LIABILITIES |  |  |
Subordinated Debt | [3] | 296,275 |
Accrued Liabilities, Fair Value Disclosure | [3] | 313,553 |
Significant Other Observable Inputs (Level 2) | Deposits [Member] |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [2] | 16,875,881 | 12,558,632
Significant Other Observable Inputs (Level 2) | Time certificates of deposits (f) |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [3] | 3,414,295 | 2,739,606
Significant Other Observable Inputs (Level 2) | Federal Home Loan Bank and other borrowings (f) |  |  |
LIABILITIES |  |  |
Federal Home Loan Bank Borrowings, Fair Value Disclosure | [3] | 404,268 | 638,489
Significant Other Observable Inputs (Level 2) | Junior subordinated debentures (g) |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [4] | 62,416 | 61,661
Significant Unobservable Inputs (Level 3) | Estimate of Fair Value Measurement |  |  |
ASSETS |  |  |
Loans Receivable, Fair Value Disclosure | [1] | 17,551,952 | 13,213,596
Significant Unobservable Inputs (Level 3) | Subordinated debentures (f) |  |  |
LIABILITIES |  |  |
Accrued Liabilities, Fair Value Disclosure | [3] | 313,553 |
U.S. treasury securities |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [5] | 100,851 | 100,791
Held to Maturity, Fair Value, Total | [5] | 96,324 | 93,022
U.S. treasury securities | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [5] | 96,324 | 93,022
Agency mortgage-backed securities |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [5] | 759,083 | 788,470
Held to Maturity, Fair Value, Total | [5] | 719,230 | 726,362
Agency mortgage-backed securities | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [5] | 719,230 | 726,362
Agency collateralized mortgage obligations |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [5] | 382,615 | 422,827
Held to Maturity, Fair Value, Total | [5] | 334,666 | 357,684
Agency collateralized mortgage obligations | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [5] | 334,666 | 357,684
Small Business Administration Pooled Securities [Member] |  |  |
ASSETS |  |  |
Debt Securities, Held-to-maturity | [5] | 115,068 | 122,868
Held to Maturity, Fair Value, Total | [5] | 110,532 | 114,733
Small Business Administration Pooled Securities [Member] | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Held to Maturity, Fair Value, Total | [5] | 110,532 | 114,733
Investment in Federal Home Loan Bank Stock [Member] |  |  |
ASSETS |  |  |
Federal Home Loan Bank Stock | [6] | 21,835 | 31,573
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | [6] | 21,835 | 31,573
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] | 21,835 | 31,573
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 |
Cash Surrender Value [Member] |  |  |
ASSETS |  |  |
Cash Surrender Value, Fair Value Disclosure | [7] | 376,163 | 303,965
Bank Owned Life Insurance | [7] | 376,163 | 303,965
Cash Surrender Value [Member] | Significant Other Observable Inputs (Level 2) |  |  |
ASSETS |  |  |
Cash Surrender Value, Fair Value Disclosure | [7] | $ 376,163 | $ 303,965
[1] | 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 non-recurring basis.
[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 by discounting anticipated future cash payments using rates currently available for instruments with similar remaining maturities.
[4] | Fair value was determined based upon market prices of securities with similar terms and maturities.
[5] | 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.
[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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- Definition Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-10 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name Accounting Standards Codification -Section 55 -Paragraph 10 -SubTopic 10 -Topic 825 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482881/825-10-55-10 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-10 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482881/825-10-55-12 + Details
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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