Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Condensed Consolidated Statements of Comprehensive Income
Net income	$ 95,221	$ 51,565	$ 34,396	$ 137,392
Unrealized gains on available for sale securities:
Unrealized holding gains arising during period	1,915	7,467	48,573	44,528
Tax effect	(421)	(1,643)	(10,686)	(9,796)
Reclassification adjustment for (gains) losses included in net income	(15)	(437)	(15)	2,679
Tax effect	3	96	3	(590)
Net of tax amount	1,482	5,483	37,875	36,821
Unrealized gains (losses) on derivative financial instruments qualifying as cash flow hedges:
Unrealized holding gains (losses) arising during period	165	(4,988)	(34,150)	(18,931)
Tax effect	(37)	1,097	7,512	4,165
Reclassification adjustment for losses (gains) included in interest expense	3,457	(241)	6,143	(585)
Tax effect	(760)	53	(1,351)	128
Net of tax amount	2,825	(4,079)	(21,846)	(15,223)
Change in pension plan and retiree medical plan obligation:
Reclassification adjustment for changes included in net income				7,888
Tax effect				(1,735)
Net of tax amount				6,153
Other comprehensive income, net of tax	4,307	1,404	16,029	27,751
Comprehensive income	$ 99,528	$ 52,969	$ 50,425	$ 165,143