Fair Value Measurements (Details 1) - USD ($) $ in Thousands		Sep. 30, 2025	Dec. 31, 2024
ASSETS
Trading		$ 4,611	$ 4,245
Equity		21,567	21,204
LIABILITIES
Debt Securities, Held-to-maturity, Fair Value		1,260,752	1,291,801
Federal Home Loan Bank Stock		21,835	31,573
Bank Owned Life Insurance		376,163	303,965
Federal Home Loan Bank and other borrowings (f)		416,240	638,514
Deposits [Member]
LIABILITIES
Financial Liabilities Book Value	[1]	16,875,881	12,558,632
Accrued Liabilities, Fair Value Disclosure	[1]	16,875,881	12,558,632
Bank Time Deposits [Member]
LIABILITIES
Financial Liabilities Book Value	[2]	3,419,988	2,747,346
Accrued Liabilities, Fair Value Disclosure	[2]	3,414,295	2,739,606
Federal Home Loan Bank Advances [Member]
LIABILITIES
Federal Home Loan Bank and other borrowings (f)	[2]	416,240	638,514
Federal Home Loan Bank Borrowings, Fair Value Disclosure	[2]	404,268	638,489
Junior Subordinated Debt [Member]
LIABILITIES
Accrued Liabilities, Fair Value Disclosure	[3]	62,416	61,661
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust	[3]	62,862	62,860
Reported Value Measurement
LIABILITIES
Loans Receivable, Fair Value Disclosure	[4]	18,219,929	14,294,628
Estimate of Fair Value Measurement
LIABILITIES
Loans Receivable, Fair Value Disclosure	[4]	17,551,952	13,213,596
Agency mortgage-backed securities
LIABILITIES
Debt Securities, Held-to-maturity, Fair Value		719,230	726,362
Small Business Administration Pooled Securities [Member]
LIABILITIES
Debt Securities, Held-to-maturity, Fair Value		110,532	114,733
US Treasury Securities [Member]
LIABILITIES
Debt Securities, Held-to-maturity, Fair Value		96,324	93,022
Recurring fair value measurements
ASSETS
Trading		4,611	4,245
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS		1,975,227	1,263,867
Recurring fair value measurements | Equity Securities [Member]
ASSETS
Equity		21,567	21,204
Recurring fair value measurements | U.S. government agency securities
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		217,175	209,660
Recurring fair value measurements | Agency mortgage-backed securities
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		707,265	378,161
Recurring fair value measurements | Agency collateralized mortgage obligations
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		276,177	28,995
Recurring fair value measurements | Municipal Bonds [Member]
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		14,665	194
Recurring fair value measurements | Pooled trust preferred securities issued by banks and insurers
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		1,040	1,095
Recurring fair value measurements | Small Business Administration Pooled Securities [Member]
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		38,577	40,838
Recurring fair value measurements | Loans held for sale
ASSETS
Loans Held-for-sale, Fair Value Disclosure		17,052	7,271
Recurring fair value measurements | Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset		64,764	103,958
Recurring fair value measurements | Derivative instruments
LIABILITIES
Financial and Nonfinancial Liabilities, Fair Value Disclosure		73,987	123,755
Recurring fair value measurements | US Treasury Securities [Member]
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		466,977	592,001
Recurring fair value measurements | Taxable Municipal Bonds
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		219,344
Non-recurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS		44,138	43,766
Non-recurring fair value measurements | Collateral Dependent Loans [Member]
ASSETS
Assets, Fair Value Disclosure	[5]	42,038	43,766
Non-recurring fair value measurements | Other Real Estate Owned and Other Foreclosed Assets
ASSETS
Assets, Fair Value Disclosure	[5]	2,100
Quoted Prices in Active Markets for Identical Assets (Level 1) | Recurring fair value measurements
ASSETS
Trading		4,611	4,245
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS		26,178	25,449
Quoted Prices in Active Markets for Identical Assets (Level 1) | Recurring fair value measurements | Equity Securities [Member]
ASSETS
Equity		21,567	21,204
Quoted Prices in Active Markets for Identical Assets (Level 1) | Non-recurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS		0	0
Significant Other Observable Inputs (Level 2) | Deposits [Member]
LIABILITIES
Accrued Liabilities, Fair Value Disclosure	[1]	16,875,881	12,558,632
Significant Other Observable Inputs (Level 2) | Bank Time Deposits [Member]
LIABILITIES
Accrued Liabilities, Fair Value Disclosure	[2]	3,414,295	2,739,606
Significant Other Observable Inputs (Level 2) | Federal Home Loan Bank Advances [Member]
LIABILITIES
Federal Home Loan Bank Borrowings, Fair Value Disclosure	[2]	404,268	638,489
Significant Other Observable Inputs (Level 2) | Junior Subordinated Debt [Member]
LIABILITIES
Accrued Liabilities, Fair Value Disclosure	[3]	62,416	61,661
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS		1,949,049	1,238,418
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | U.S. government agency securities
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		217,175	209,660
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | Agency mortgage-backed securities
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		707,265	378,161
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | Agency collateralized mortgage obligations
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		276,177	28,995
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | Municipal Bonds [Member]
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		14,665	194
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | Pooled trust preferred securities issued by banks and insurers
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		1,040	1,095
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | Small Business Administration Pooled Securities [Member]
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		38,577	40,838
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | Loans held for sale
ASSETS
Loans Held-for-sale, Fair Value Disclosure		17,052	7,271
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset		64,764	103,958
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | Derivative instruments
LIABILITIES
Financial and Nonfinancial Liabilities, Fair Value Disclosure		73,987	123,755
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | US Treasury Securities [Member]
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		466,977	592,001
Significant Other Observable Inputs (Level 2) | Recurring fair value measurements | Taxable Municipal Bonds
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		219,344
Significant Other Observable Inputs (Level 2) | Non-recurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS		0	0
Significant Unobservable Inputs (Level 3) | Estimate of Fair Value Measurement
LIABILITIES
Loans Receivable, Fair Value Disclosure	[4]	17,551,952	13,213,596
Significant Unobservable Inputs (Level 3) | Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS		0	0
Significant Unobservable Inputs (Level 3) | Recurring fair value measurements | Small Business Administration Pooled Securities [Member]
ASSETS
Available for sale (amortized cost $1,998,347 and $1,353,964)		0
Significant Unobservable Inputs (Level 3) | Non-recurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS		44,138	43,766
Significant Unobservable Inputs (Level 3) | Non-recurring fair value measurements | Collateral Dependent Loans [Member]
ASSETS
Assets, Fair Value Disclosure	[5]	42,038	43,766
Significant Unobservable Inputs (Level 3) | Non-recurring fair value measurements | Other Real Estate Owned and Other Foreclosed Assets
ASSETS
Assets, Fair Value Disclosure	[5]	2,100
US Treasury Securities [Member]
LIABILITIES
Debt Securities, Held-to-maturity	[6]	100,851	100,791
Debt Securities, Held-to-maturity, Fair Value	[6]	96,324	93,022
US Treasury Securities [Member] | Significant Other Observable Inputs (Level 2)
LIABILITIES
Debt Securities, Held-to-maturity, Fair Value	[6]	96,324	93,022
Agency mortgage-backed securities
LIABILITIES
Debt Securities, Held-to-maturity	[6]	759,083	788,470
Debt Securities, Held-to-maturity, Fair Value	[6]	719,230	726,362
Agency mortgage-backed securities | Significant Other Observable Inputs (Level 2)
LIABILITIES
Debt Securities, Held-to-maturity, Fair Value	[6]	719,230	726,362
Agency collateralized mortgage obligations
LIABILITIES
Debt Securities, Held-to-maturity	[6]	382,615	422,827
Debt Securities, Held-to-maturity, Fair Value	[6]	334,666	357,684
Agency collateralized mortgage obligations | Significant Other Observable Inputs (Level 2)
LIABILITIES
Debt Securities, Held-to-maturity, Fair Value	[6]	334,666	357,684
Small Business Administration Pooled Securities [Member]
LIABILITIES
Debt Securities, Held-to-maturity	[6]	115,068	122,868
Debt Securities, Held-to-maturity, Fair Value	[6]	110,532	114,733
Small Business Administration Pooled Securities [Member] | Significant Other Observable Inputs (Level 2)
LIABILITIES
Debt Securities, Held-to-maturity, Fair Value	[6]	110,532	114,733
Investment in Federal Home Loan Bank Stock [Member]
LIABILITIES
Federal Home Loan Bank Stock	[7]	21,835	31,573
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	[7]	21,835	31,573
Investment in Federal Home Loan Bank Stock [Member] | Significant Other Observable Inputs (Level 2)
LIABILITIES
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	[7]	21,835	31,573
Investment in Federal Home Loan Bank Stock [Member] | Significant Unobservable Inputs (Level 3)
LIABILITIES
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	[7]	0
Cash Surrender Value [Member]
LIABILITIES
Bank Owned Life Insurance	[8]	376,163	303,965
Cash Surrender Value, Fair Value Disclosure	[8]	376,163	303,965
Cash Surrender Value [Member] | Significant Other Observable Inputs (Level 2)
LIABILITIES
Cash Surrender Value, Fair Value Disclosure	[8]	$ 376,163	$ 303,965

[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] 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.

[5] The carrying value of individually assessed collateral dependent loans is based on the lower of amortized cost or fair value of the underlying collateral less costs to sell. The fair value of the underlying collateral is generally determined through independent appraisals, which generally include various Level 3 inputs which are not identifiable. Appraisals may be adjusted by management for qualitative factors such as economic factors and estimated liquidation expenses. The range of these possible adjustments may vary.

[6] 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.

[7] Federal Home Loan Bank stock has no quoted market value and is carried at cost; therefore, the carrying amount approximates fair value.

[8] 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.