Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 37,268	$ 27,143	$ 130,618	$ 56,384
Unrealized gains and losses on available for sale debt securities:
Net unrealized (losses) gains arising during the period	(7,990)	(428)	(14,569)	15,388
Reclassification adjustment for gains included in net income	0	0	(171)	0
Total	(7,990)	(428)	(14,740)	15,388
Unrealized gains (losses) on derivatives	1,768	880	5,165	(6,117)
Amortization related to post-retirement obligations	(103)	85	(323)	239
Total other comprehensive (loss) income	(6,325)	537	(9,898)	9,510
Total comprehensive income	$ 30,943	$ 27,680	$ 120,720	$ 65,894