Shareholders' Equity - Changes in Balances of Component of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 1,661,847	$ 1,492,268	$ 1,741,311
Other comprehensive income (loss) before reclassification	(14,888)	43,185	(244,088)
Amounts reclassified from accumulated other comprehensive income (loss)	150,952	12,495	1,245
Other comprehensive income (loss), net of tax amount	136,064	55,680	(242,843)
Balance	1,962,327	1,661,847	1,492,268
Securities Available for Sale and Transferred Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(204,670)	(254,442)	(17,774)
Other comprehensive income (loss) before reclassification	691	49,801	(236,668)
Amounts reclassified from accumulated other comprehensive income (loss)	137,094	(29)	0
Other comprehensive income (loss), net of tax amount	137,785	49,772	(236,668)
Balance	(66,885)	(204,670)	(254,442)
Defined Benefit Pension Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(6,075)	(5,792)	(14,786)
Other comprehensive income (loss) before reclassification	1,095	(518)	8,094
Amounts reclassified from accumulated other comprehensive income (loss)	259	235	900
Other comprehensive income (loss), net of tax amount	1,354	(283)	8,994
Balance	(4,721)	(6,075)	(5,792)
Cash Flow Hedge Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(8,978)	(15,169)	0
Other comprehensive income (loss) before reclassification	(16,674)	(6,098)	(15,514)
Amounts reclassified from accumulated other comprehensive income (loss)	13,599	12,289	345
Other comprehensive income (loss), net of tax amount	(3,075)	6,191	(15,169)
Balance	(12,053)	(8,978)	(15,169)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(219,723)	(275,403)	(32,560)
Balance	$ (83,659)	$ (219,723)	$ (275,403)