Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income per consolidated statements of income	$ 34,284	$ 47,981	$ 63,495	$ 99,943
Net unrealized gains (losses) on available for sale securities and transferred securities:
Net unrealized holding gains (losses) arising during the period	(33,397)	4,959	(150,150)	(11,391)
Change in net unrealized holding loss on securities transferred to held to maturity	(25,338)	552	(24,938)	1,085
Reclassification adjustments for changes realized in net income:
Net change in prior service costs	21	21	41	42
Change in net actuarial loss	228	333	465	674
Other comprehensive income (loss), net of tax	(58,486)	5,865	(174,582)	(9,590)
Comprehensive income (loss)	$ (24,202)	$ 53,846	$ (111,087)	$ 90,353