Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 92,049	$ 57,603	$ 54,717
Other comprehensive income (loss), net of tax:
Unrealized (loss) gain on debt securities available for sale	(30,979)	21,236	21,067
Accretion of unrealized (loss) gain on debt securities reclassified as held to maturity	(3)	126	9
Reclassification adjustment for gain included in net income	1,598	289	2,011
Total other comprehensive (loss) income, available-for-sale securities and held-to-maturity adjustments, net of tax	(29,384)	21,651	23,087
Derivatives, net of tax:
Unrealized gain (loss) on swap contracts accounted for as cash flow hedges	11,939	(8,382)	(6,468)
Total derivative, net of tax	11,939	(8,382)	(6,468)
Employee benefit plans, net of tax:
Amortization of prior service cost included in net income	(39)	(44)	(44)
Reclassification adjustment of actuarial net (loss) included in net income	(2,915)	(3,384)	(2,930)
Change in funded status of retirement obligations	44,105	(10,731)	(9,935)
Total employee benefit plans, net of tax	41,151	(14,159)	(12,909)
Total other comprehensive income (loss)	23,706	(890)	3,710
Total comprehensive income, net of tax	$ 115,755	$ 56,713	$ 58,427