Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 97,738	$ 135,389	$ 341,999	$ 380,302
Other comprehensive income (loss) before income taxes:
Net change in unrealized loss on securities available for sale cash flow hedges and equity method investment	(184,530)	(367,437)	(187,089)	(961,892)
Reclassification of (income) loss realized and included in earnings	12,854	(1,441)	33,619	(10,849)
Valuation adjustments to employee benefit plans	214	(410)	(7,307)	(8,397)
Amortization of unrealized net loss on securities transferred to held to maturity	421	434	1,343	961
Other comprehensive loss before income taxes	(171,041)	(368,854)	(159,434)	(980,177)
Income tax benefit	(38,833)	(83,250)	(36,622)	(221,331)
Other comprehensive loss net of income taxes	(132,208)	(285,604)	(122,812)	(758,846)
Comprehensive income (loss)	$ (34,470)	$ (150,215)	$ 219,187	$ (378,544)