Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Commitments And Contingencies [Line Items]
Letters of credit outstanding	$ 389,500	$ 344,400
Mortgage loans sold	1,963,214	3,146,442	$ 7,441,705
Liability for estimated losses on repurchase and indemnification claims	152	624
Losses charged against liability	96	60
Unfunded commitments to investment partnerships	54,000	50,900
Commitments to invest in partnership for tax credits	36,200	7,100
Customer balances maintained by clearing broker and subject to indemnification	9,000	15,800
Forward contracts
Commitments And Contingencies [Line Items]
Derivative instrument, contractual amounts	626,900	321,000
Commercial, commercial real estate, and construction loans | Commitments to extend credit
Commitments And Contingencies [Line Items]
Commitments to fund	10,500,000	9,500,000
Unused home equity lines | Commitments to extend credit
Commitments And Contingencies [Line Items]
Commitments to fund	845,600	796,900
Residential real estate | Commitments to extend credit
Commitments And Contingencies [Line Items]
Commitments to fund	$ 222,800	$ 181,000