Accumulated Other Comprehensive Loss - Changes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Pre-tax Amount
Other comprehensive income , Pre-tax Amount	$ 6,338	$ (1,441)	$ 15,108	$ 36,166
Income Tax Benefit (Expense)
Other comprehensive loss, Income Tax Benefit (Expense)	(1,690)	384	(4,030)	(9,648)
Net of tax
Balance	2,513,761	2,329,012	2,486,066	2,269,005
Other comprehensive income (loss)	4,648	(1,057)	11,078	26,518
Balance	2,550,312	2,359,738	2,550,312	2,359,738
Accumulated Other Comprehensive Income (Loss)
Pre-tax Amount
Accumulated other comprehensive loss, beginning balance, Pre-tax Amount	(714,330)	(834,206)	(723,100)	(871,813)
Accumulated other comprehensive loss, ending balance, Pre-tax Amount	(707,992)	(835,647)	(707,992)	(835,647)
Income Tax Benefit (Expense)
Accumulated other comprehensive loss, beginning balance, Income Tax Benefit (Expense)	190,550	222,527	192,890	232,559
Accumulated other comprehensive loss, ending balance, Income Tax Benefit (Expense)	188,860	222,911	188,860	222,911
Net of tax
Balance	(523,780)	(611,679)	(530,210)	(639,254)
Other comprehensive income (loss)	4,648	(1,057)	11,078	26,518
Balance	(519,132)	(612,736)	(519,132)	(612,736)
Investment securities
Pre-tax Amount
Unrealized net gains (losses) arising during the period, Pre-tax Amount	(4,277)	(14,025)	(7,709)	11,013
Other comprehensive income , Pre-tax Amount	6,388	(961)	14,116	35,785
Income Tax Benefit (Expense)
Unrealized net gains (losses) arising during the period, Income Tax Benefit (Expense)	1,141	3,741	2,056	(2,938)
Other comprehensive loss, Income Tax Benefit (Expense)	(1,704)	256	(3,765)	(9,546)
Net of tax
Unrealized net gains (losses) arising during the period, Net of tax	(3,136)	(10,284)	(5,653)	8,075
Other comprehensive income (loss)	4,684	(705)	10,351	26,239
Amortization of unrealized holding losses on held-to-maturity securities
Pre-tax Amount
Reclassification of net losses (gains) to net income, Pre-tax Amount	10,665	13,064	21,825	24,772
Income Tax Benefit (Expense)
Reclassification of net (losses) gains to net income, Income Tax Benefit (Expense)	(2,845)	(3,485)	(5,821)	(6,608)
Net of tax
Reclassification of net gains (losses) to net income, Net of tax	7,820	9,579	16,004	18,164
Cash flow derivative hedges
Pre-tax Amount
Unrealized net gains (losses) arising during the period, Pre-tax Amount	(113)	(2,053)	(826)	(2,495)
Reclassification of net losses (gains) to net income, Pre-tax Amount	63	1,573	1,818	2,876
Other comprehensive income , Pre-tax Amount	(50)	(480)	992	381
Income Tax Benefit (Expense)
Unrealized net gains (losses) arising during the period, Income Tax Benefit (Expense)	31	548	220	665
Reclassification of net (losses) gains to net income, Income Tax Benefit (Expense)	(17)	(420)	(485)	(767)
Other comprehensive loss, Income Tax Benefit (Expense)	14	128	(265)	(102)
Net of tax
Balance	(40)	(4,071)	(803)	(4,702)
Unrealized net gains (losses) arising during the period, Net of tax	(82)	(1,505)	(606)	(1,830)
Reclassification of net gains (losses) to net income, Net of tax	46	1,153	1,333	2,109
Other comprehensive income (loss)	(36)	(352)	727	279
Balance	$ (76)	$ (4,423)	$ (76)	$ (4,423)