Mortgage Servicing Rights Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Servicing Assets at Amortized Value [Line Items]
Loans serviced by unrelated third party	$ 4,100,000	$ 4,200,000
Estimated fair value of MSRs	49,700	50,000
Non-interest income before investment securities gains	228,411	227,157	$ 240,229
Mortgage banking
Servicing Assets at Amortized Value [Line Items]
Non-interest income before investment securities gains	10,388	14,204	33,576
Residential mortgage
Servicing Assets at Amortized Value [Line Items]
Estimated fair value of MSRs	49,696	50,044	35,393
Increase to valuation allowance	0	0	600	$ 10,500
Amortization expense	5,090	5,843	11,968
Residential mortgage | Mortgage banking
Servicing Assets at Amortized Value [Line Items]
Non-interest income before investment securities gains	$ 10,200	$ 10,600	$ 11,200