Shareholders' Equity and Other Comprehensive Income (Loss) (Changes in Accumulated Other Comprehensive Income (Loss) by Component (Net of Income Taxes)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	$ 4,584,438	$ 5,237,714	$ 5,296,800	$ 5,161,334
Total other comprehensive income (loss), net of tax	(507,609)	(51,188)	(1,451,993)	(164,097)
Ending balance	4,229,715	5,252,802	4,229,715	5,252,802
Accumulated other comprehensive loss	1,534,314		1,534,314		$ 82,321
Total
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	(1,026,705)	45,726	(82,321)	158,635
Other comprehensive income (loss) before reclassifications	(515,420)	(47,474)	(1,448,523)	(157,937)
Amounts reclassified from AOCI	7,811	(3,714)	(3,470)	(6,160)
Total other comprehensive income (loss), net of tax	(507,609)	(51,188)	(1,451,993)	(164,097)
Ending balance	(1,534,314)	(5,462)	(1,534,314)	(5,462)
Net unrealized gains (losses) on investment securities available for sale
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	(869,519)	19,301	(67,980)	105,669
Other comprehensive income (loss) before reclassifications	(430,453)	(41,437)	(1,231,992)	(129,280)
Amounts reclassified from AOCI	0	(719)	0	756
Total other comprehensive income (loss), net of tax	(430,453)	(42,156)	(1,231,992)	(128,524)
Ending balance	(1,299,972)	(22,855)	(1,299,972)	(22,855)
Accumulated other comprehensive loss	13,300		13,300
Net unrealized gains (losses) on cash flow hedges
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	(157,186)	26,425	(14,341)	52,966
Other comprehensive income (loss) before reclassifications	(84,967)	(6,037)	(216,531)	(28,657)
Amounts reclassified from AOCI	7,811	(2,995)	(3,470)	(6,916)
Total other comprehensive income (loss), net of tax	(77,156)	(9,032)	(220,001)	(35,573)
Ending balance	(234,342)	$ 17,393	(234,342)	$ 17,393
Accumulated other comprehensive loss	$ 12,100		$ 12,100