Investment Securities - Amortized Cost and Fair Value of Securities (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Available for sale debt securities
Amortized Cost	$ 3,549,599,000	$ 8,560,733,000
Unrealized Gains	50,000	24,595,000
Unrealized Losses	(398,516,000)	(157,296,000)
Total available-for-sale securities, Fair value,	3,151,133,000	8,428,032,000
Held to maturity securities
Amortized Cost	4,320,639,000
Unrealized Losses	(505,817,000)
Total held to maturity, Fair value,	3,814,822,000	0
Available-for-sale investment securities
Accrued interest receivable related to available-for-sale investment securities	$ 8,900,000	$ 14,100,000
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest Receivable	Interest Receivable
Accrued interest receivable related to held to maturity investment securities	$ 7,500,000	$ 0
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest Receivable	Interest Receivable
Reclassification of available for sale securities to held to maturity	$ 4,600,000,000
Other comprehensive income (loss), transfer of securities from available for sale to held to maturity	(372,400,000)
Gain (loss) recognized on reclassification, transfer of securities from available for sale to held to maturity	$ 0
Securities held-to-maturity, weighted average life	8 years 2 months 12 days
Collateralized Loan Obligations
Available for sale debt securities
Amortized Cost	$ 249,877,000	$ 105,245,000
Unrealized Gains	50,000	2,000
Unrealized Losses	(8,606,000)
Total available-for-sale securities, Fair value,	241,321,000	105,247,000
U.S. Treasury and government agency debt securities
Available for sale debt securities
Amortized Cost	163,309,000	196,662,000
Unrealized Gains		125,000
Unrealized Losses	(12,327,000)	(4,224,000)
Total available-for-sale securities, Fair value,	150,982,000	192,563,000
Government-sponsored enterprises debt securities
Available for sale debt securities
Amortized Cost	45,000,000
Unrealized Losses	(699,000)
Total available-for-sale securities, Fair value,	44,301,000
Government agency debt securities
Held to maturity securities
Amortized Cost	54,318,000
Unrealized Losses	(5,674,000)
Total held to maturity, Fair value,	48,644,000
Residential - Government agency
Available for sale debt securities
Amortized Cost	66,792,000	135,764,000
Unrealized Gains		1,791,000
Unrealized Losses	(7,069,000)	(291,000)
Total available-for-sale securities, Fair value,	59,723,000	137,264,000
Held to maturity securities
Amortized Cost	46,302,000
Unrealized Losses	(6,294,000)
Total held to maturity, Fair value,	40,008,000
Residential - Government-sponsored enterprises
Available for sale debt securities
Amortized Cost	1,317,718,000	1,496,605,000
Unrealized Gains		6,914,000
Unrealized Losses	(157,263,000)	(12,419,000)
Total available-for-sale securities, Fair value,	1,160,455,000	1,491,100,000
Held to maturity securities
Amortized Cost	106,534,000
Unrealized Losses	(12,978,000)
Total held to maturity, Fair value,	93,556,000
Commercial - Government agency
Available for sale debt securities
Amortized Cost	282,700,000	392,443,000
Unrealized Gains		1,741,000
Unrealized Losses	(44,847,000)	(6,521,000)
Total available-for-sale securities, Fair value,	237,853,000	387,663,000
Held to maturity securities
Amortized Cost	30,544,000
Unrealized Losses	(5,229,000)
Total held to maturity, Fair value,	25,315,000
Commercial - Government-sponsored enterprises
Available for sale debt securities
Amortized Cost	130,612,000	1,415,511,000
Unrealized Gains		2,646,000
Unrealized Losses	(11,039,000)	(48,714,000)
Total available-for-sale securities, Fair value,	119,573,000	1,369,443,000
Held to maturity securities
Amortized Cost	1,150,449,000
Unrealized Losses	(138,451,000)
Total held to maturity, Fair value,	1,011,998,000
Commercial - Non -agency
Available for sale debt securities
Amortized Cost	21,964,000
Unrealized Losses	(493,000)
Total available-for-sale securities, Fair value,	21,471,000
Government agency
Available for sale debt securities
Amortized Cost	738,524,000	2,103,187,000
Unrealized Gains		7,768,000
Unrealized Losses	(85,202,000)	(31,432,000)
Total available-for-sale securities, Fair value,	653,322,000	2,079,523,000
Held to maturity securities
Amortized Cost	1,080,492,000
Unrealized Losses	(122,378,000)
Total held to maturity, Fair value,	958,114,000
Government-sponsored enterprises
Available for sale debt securities
Amortized Cost	533,103,000	2,671,131,000
Unrealized Gains		3,608,000
Unrealized Losses	(70,971,000)	(53,695,000)
Total available-for-sale securities, Fair value,	462,132,000	2,621,044,000
Held to maturity securities
Amortized Cost	1,798,178,000
Unrealized Losses	(207,045,000)
Total held to maturity, Fair value,	1,591,133,000
Debt securities issued by states and political subdivisions
Available for sale debt securities
Amortized Cost		44,185,000
Total available-for-sale securities, Fair value,		$ 44,185,000
Held to maturity securities
Amortized Cost	53,822,000
Unrealized Losses	(7,768,000)
Total held to maturity, Fair value,	$ 46,054,000

Amount of gain (loss) recognized on reclassification of available for sale securities to held to maturity.

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