CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 120,512	$ 95,601	$ 236,222	$ 182,869
Unrealized gains and losses on available for sale securities
Net (losses) gains arising during the period	(1,471)	3,013	(11,907)	29,081
Less reclassification adjustment for net losses included in net income	76	31	120	58
Total	(1,395)	3,044	(11,787)	29,139
Unrealized gains and losses on derivatives (cash flow hedges)
Net (losses) gains on derivatives arising during the period	(147)	(1,280)	27	(2,337)
Less reclassification adjustment for net losses (gains) included in net income	534	(308)	1,185	130
Total	387	(1,588)	1,212	(2,207)
Defined benefit pension plan
Amortization of actuarial net loss	278	172	558	344
Total other comprehensive (loss) income	(730)	1,628	(10,017)	27,276
Total comprehensive income	$ 119,782	$ 97,229	$ 226,205	$ 210,145