Goodwill and Other Intangible Assets, Mortgage Servicing Rights Roll-Forward (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2023
Summary of Changes in MSR [Line Items]
Servicing Asset at Fair Value, Amount, Beginning Balance	$ 84,390		$ 77,351	$ 77,351
Additions	877		474	3,564
Paydowns	(1,687)			(7,185)
Change in fair value model assumptions	0			8,881
Changes in fair value of asset	1,646			1,778
Servicing Asset at Fair Value, Amount, Ending Balance	85,226	$ 84,390		84,390
Portfolio Of Residential Mortgage Loans Serviced For Others	$ 6,349,049	$ 7,364,492		$ 7,364,492
Mortgage Servicing Rights Net To Servicing Portfolio	1.34%	1.15%		1.15%
Loans transferred (from) into held for sale from (into) portfolio, net	$ (86,096)		$ 94
Residential mortgage
Summary of Changes in MSR [Line Items]
Loans transferred (from) into held for sale from (into) portfolio, net		$ 969,000
Proceeds from Sale, Loan, Held-for-Sale		$ 844,000

Mortgage servicing rights, net to servicing portfolio.

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Portfolio of residential mortgage loans serviced for others ("servicing portfolio").

+ References

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Summary of Changes in MSR

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- Definition

The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
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- Definition

The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of increase (decrease) in fair value from changes in the inputs, assumptions, or model used to calculate the fair value of the contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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- Definition

Decrease in servicing assets subsequently measured at fair value resulting from conveyance of servicing rights to unrelated parties.

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Amount of increase (decrease) from changes in fair value classified as other for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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- Definition

Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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