Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Total temporarily impaired securities, Duration Unrealized Loss Position, Less Than Twelve Months, Fair Value	$ 527,773	$ 726,921
Total temporarily impaired securities, Duration of Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Loss	(65,367)	(12,916)
Total temporarily impaired securities, Duration of Unrealized Loss Position, Twelve Months or Longer, Fair Value	492,189	51,446
Total temporarily impaired securities, Duration of Unrealized Loss Position, Twelve Months or Longer, Gross Unrealized Loss	(123,071)	(2,043)
Total temporarily impaired securities, Duration of Unrealized Loss Position, Fair Value	1,019,962	778,367
Total temporarily impaired securities, Duration of Unrealized Loss Position, Unrealized Loss	(188,438)	(14,959)
Obligations of U.S. government corporations and agencies [Member]
Available-for-sale securities, Duration of Unrealized Loss Position, Less than 12 Month, Fair Value	99,589	73,810
Available-for-sale Securities, Duration of Unrealized Loss Position, Less than 12 Month, Gross Unrealized Loss	(19,180)	(918)
Available-for-sale securities, Duration of Unrealized Loss Position, 12 Month or Longer, Fair Value	44,436	0
Available-for-sale Securities, Duration of Unrealized Loss Position, 12 Month or Longer, Gross Unrealized Loss	(10,702)	0
Available-for-sale securities, Total, Fair Value	144,025	73,810
Available-for-sale securities, Total, Unrealized Loss	(29,882)	(918)
Mortgage-Backed Securities [Member]
Available-for-sale securities, Duration of Unrealized Loss Position, Less than 12 Month, Fair Value	48,282	167,379
Available-for-sale Securities, Duration of Unrealized Loss Position, Less than 12 Month, Gross Unrealized Loss	(5,761)	(2,048)
Available-for-sale securities, Duration of Unrealized Loss Position, 12 Month or Longer, Fair Value	120,826	13,689
Available-for-sale Securities, Duration of Unrealized Loss Position, 12 Month or Longer, Gross Unrealized Loss	(29,786)	(333)
Available-for-sale securities, Total, Fair Value	169,108	181,068
Available-for-sale securities, Total, Unrealized Loss	(35,547)	(2,381)
Collateralized mortgage obligations [Member]
Available-for-sale securities, Duration of Unrealized Loss Position, Less than 12 Month, Fair Value	111,746	222,134
Available-for-sale Securities, Duration of Unrealized Loss Position, Less than 12 Month, Gross Unrealized Loss	(14,355)	(4,736)
Available-for-sale securities, Duration of Unrealized Loss Position, 12 Month or Longer, Fair Value	145,309	0
Available-for-sale Securities, Duration of Unrealized Loss Position, 12 Month or Longer, Gross Unrealized Loss	(35,213)	0
Available-for-sale securities, Total, Fair Value	257,055	222,134
Available-for-sale securities, Total, Unrealized Loss	(49,568)	(4,736)
Corporate bonds [Member]
Available-for-sale securities, Duration of Unrealized Loss Position, Less than 12 Month, Fair Value	57,170	24,173
Available-for-sale Securities, Duration of Unrealized Loss Position, Less than 12 Month, Gross Unrealized Loss	(4,946)	(270)
Available-for-sale securities, Duration of Unrealized Loss Position, 12 Month or Longer, Fair Value	10,252	504
Available-for-sale Securities, Duration of Unrealized Loss Position, 12 Month or Longer, Gross Unrealized Loss	(1,291)	(5)
Available-for-sale securities, Total, Fair Value	67,422	24,677
Available-for-sale securities, Total, Unrealized Loss	(6,237)	(275)
Obligations of state and political subdivisions [Member]
Available-for-sale securities, Duration of Unrealized Loss Position, Less than 12 Month, Fair Value	128,802	99,199
Available-for-sale Securities, Duration of Unrealized Loss Position, Less than 12 Month, Gross Unrealized Loss	(19,309)	(3,355)
Available-for-sale securities, Duration of Unrealized Loss Position, 12 Month or Longer, Fair Value	89,875	34,548
Available-for-sale Securities, Duration of Unrealized Loss Position, 12 Month or Longer, Gross Unrealized Loss	(39,381)	(1,675)
Available-for-sale securities, Total, Fair Value	218,677	133,747
Available-for-sale securities, Total, Unrealized Loss	(58,690)	(5,030)
Asset-backed securities [Member]
Available-for-sale securities, Duration of Unrealized Loss Position, Less than 12 Month, Fair Value	82,184	140,226
Available-for-sale Securities, Duration of Unrealized Loss Position, Less than 12 Month, Gross Unrealized Loss	(1,816)	(1,589)
Available-for-sale securities, Duration of Unrealized Loss Position, 12 Month or Longer, Fair Value	81,491	2,705
Available-for-sale Securities, Duration of Unrealized Loss Position, 12 Month or Longer, Gross Unrealized Loss	(6,698)	(30)
Available-for-sale securities, Total, Fair Value	163,675	142,931
Available-for-sale securities, Total, Unrealized Loss	$ (8,514)	$ (1,619)