Investment Securities - Summary of available-for-sale securities - (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Marketable Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	$ 1,251,562	$ 1,211,353
Available-for-Sale Securities, Gross Unrealized Gains	589	9,866
Available-for-Sale Securities, Gross Unrealized Loss	(188,438)	(14,959)
Available-for-Sale Securities, Fair Value	1,063,713	1,206,260
Obligations of U.S. government corporations and agencies [Member]
Marketable Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	173,907	174,644
Available-for-Sale Securities, Gross Unrealized Gains	0	984
Available-for-Sale Securities, Gross Unrealized Loss	(29,882)	(918)
Available-for-Sale Securities, Fair Value	144,025	174,710
Mortgage-Backed Securities [Member]
Marketable Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	204,655	208,281
Available-for-Sale Securities, Gross Unrealized Gains		851
Available-for-Sale Securities, Gross Unrealized Loss	(35,547)	(2,381)
Available-for-Sale Securities, Fair Value	169,108	206,751
Collateralized mortgage obligations [Member]
Marketable Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	306,623	264,541
Available-for-Sale Securities, Gross Unrealized Gains	0	363
Available-for-Sale Securities, Gross Unrealized Loss	(49,568)	(4,736)
Available-for-Sale Securities, Fair Value	257,055	260,168
Asset-backed securities [Member]
Marketable Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	206,505	221,545
Available-for-Sale Securities, Gross Unrealized Gains	557	610
Available-for-Sale Securities, Gross Unrealized Loss	(8,514)	(1,619)
Available-for-Sale Securities, Fair Value	198,548	220,536
Corporate bonds [Member]
Marketable Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	73,659	70,008
Available-for-Sale Securities, Gross Unrealized Gains		1,160
Available-for-Sale Securities, Gross Unrealized Loss	(6,237)	(275)
Available-for-Sale Securities, Fair Value	67,422	70,893
Obligations of state and political subdivisions [Member]
Marketable Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	286,213	272,334
Available-for-Sale Securities, Gross Unrealized Gains	32	5,898
Available-for-Sale Securities, Gross Unrealized Loss	(58,690)	(5,030)
Available-for-Sale Securities, Fair Value	$ 227,555	$ 273,202

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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Amortized cost of 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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