Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Balance at the beginning of the period	$ 1,697,096	$ 1,619,797	$ 1,413,840
Current period change in other comprehensive (loss) income	(171,908)	(10,792)	13,834
Balance at the end of the period	1,597,703	1,697,096	1,619,797
Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Balance at the beginning of the period			(8,311)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Balance at the beginning of the period	6,863	17,655	3,821
Current period change in other comprehensive (loss) income	(171,908)	(10,792)	13,834
Balance at the end of the period	(165,045)	6,863	17,655
Unrealized Losses on Available for Sale Debt Securities
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Balance at the beginning of the period	(211)	23,690
Current period change in other comprehensive (loss) income	(186,403)	(23,901)
Balance at the end of the period	(186,614)	(211)	23,690
Post-Retirement Obligations
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Balance at the beginning of the period	2,981	(1,081)
Current period change in other comprehensive (loss) income	(1,409)	4,062
Balance at the end of the period	1,572	2,981	(1,081)
Unrealized Gains on Derivatives (cash flow hedges)
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Balance at the beginning of the period	4,093	(4,954)
Current period change in other comprehensive (loss) income	15,904	9,047
Balance at the end of the period	$ 19,997	$ 4,093	$ (4,954)