Securities - Amortized Cost and Estimated Fair Value of Securities Available-for-Sale and Held-to-Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Securities Financing Transaction [Line Items]
Available-for-sale, amortized cost	$ 503,404	$ 569,874
Available-for-sale, gross unrealized gains	1	1,275
Available-for-sale, gross unrealized losses	(45,757)	(2,894)
Available-for-sale, fair value	457,648	568,255
Allowance for securities credit losses	0	0
Amortized Cost	1,224,564	1,143,548
Held-to-maturity, gross unrealized losses	1,244	18,967
Held-to-maturity, gross unrealized losses	(115,767)	(9,771)
Debt securities held-to-maturity	1,110,041	1,152,744
Allowance for securities credit losses	(1,128)	(1,467)	$ (1,715)
Total, amortized cost	1,727,968	1,713,422
Total, gross unrealized gains	1,245	20,242
Total, gross unrealized losses	(161,524)	(12,665)
Total, estimated fair value	1,567,689	1,720,999
U.S. government and agency obligations
Securities Financing Transaction [Line Items]
Available-for-sale, amortized cost	87,648	164,756
Available-for-sale, gross unrealized gains	1	1,135
Available-for-sale, gross unrealized losses	(7,635)	(471)
Available-for-sale, fair value	80,014	165,420
Allowance for securities credit losses	0	0
Corporate debt securities
Securities Financing Transaction [Line Items]
Available-for-sale, amortized cost	8,928	5,000
Available-for-sale, gross unrealized gains	0	42
Available-for-sale, gross unrealized losses	(756)	(11)
Available-for-sale, fair value	8,172	5,031
Allowance for securities credit losses	0	0
Amortized Cost	56,893	68,823
Held-to-maturity, gross unrealized losses	380	1,628
Held-to-maturity, gross unrealized losses	(3,778)	(1,279)
Debt securities held-to-maturity	53,495	69,172
Allowance for securities credit losses	(1,059)	(1,343)
Asset-backed securities
Securities Financing Transaction [Line Items]
Available-for-sale, amortized cost	296,222	298,976
Available-for-sale, gross unrealized gains	0	41
Available-for-sale, gross unrealized losses	(19,349)	(1,489)
Available-for-sale, fair value	276,873	297,528
Allowance for securities credit losses	0	0
Agency commercial MBS
Securities Financing Transaction [Line Items]
Available-for-sale, amortized cost	110,606	101,142
Available-for-sale, gross unrealized gains	0	57
Available-for-sale, gross unrealized losses	(18,017)	(923)
Available-for-sale, fair value	92,589	100,276
Allowance for securities credit losses	0	0
Amortized Cost	32,127	4,385
Held-to-maturity, gross unrealized losses	23	7
Held-to-maturity, gross unrealized losses	(1,189)	(44)
Debt securities held-to-maturity	30,961	4,348
Allowance for securities credit losses	0	0
State, municipal and sovereign debt obligations
Securities Financing Transaction [Line Items]
Amortized Cost	260,249	281,389
Held-to-maturity, gross unrealized losses	46	10,185
Held-to-maturity, gross unrealized losses	(24,940)	(1,164)
Debt securities held-to-maturity	235,355	290,410
Allowance for securities credit losses	(60)	(85)
Agency residential
Securities Financing Transaction [Line Items]
Amortized Cost	849,985	756,844
Held-to-maturity, gross unrealized losses	795	6,785
Held-to-maturity, gross unrealized losses	(83,586)	(7,180)
Debt securities held-to-maturity	767,194	756,449
Allowance for securities credit losses	0	0
Non-agency commercial
Securities Financing Transaction [Line Items]
Amortized Cost	25,310	32,107
Held-to-maturity, gross unrealized losses	0	362
Held-to-maturity, gross unrealized losses	(2,274)	(104)
Debt securities held-to-maturity	23,036	32,365
Allowance for securities credit losses	(9)	(39)
Total mortgage-backed securities
Securities Financing Transaction [Line Items]
Amortized Cost	907,422	793,336
Held-to-maturity, gross unrealized losses	818	7,154
Held-to-maturity, gross unrealized losses	(87,049)	(7,328)
Debt securities held-to-maturity	821,191	793,162
Allowance for securities credit losses	$ (9)	$ (39)

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Available For Sale Securities And Held To Maturity Securities Estimated Fair Value

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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