Loans and Allowance for Loan Losses - Schedule of Allowances For Loan Losses and Recorded Investment In Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Allowance for loan losses:
Beginning balance	$ 479,385	$ 443,424	$ 443,424
Charge-offs	(50,568)	(25,335)	(183,074)
Recoveries	6,212	6,785
Provision for (reversal of) loan losses	57,632	32,136
Ending balance	492,661	457,010	479,385
Commercial & Industrial
Allowance for loan losses:
Beginning balance	218,970	161,550	161,550
Charge-offs	(37,943)	(7,873)
Recoveries	3,288	3,476
Provision for (reversal of) loan losses	29,167	1,535
Ending balance	213,482	158,688	218,970
Commercial Real Estate
Allowance for loan losses:
Beginning balance	133,758	143,575	143,575
Charge-offs	(3,711)	(96)
Recoveries	767	284
Provision for (reversal of) loan losses	21,813	16,629
Ending balance	152,627	160,392	133,758
Total consumer
Allowance for loan losses:
Beginning balance	126,657	138,299	138,299
Charge-offs	(8,914)	(17,366)
Recoveries	2,157	3,025
Provision for (reversal of) loan losses	6,652	13,972
Ending balance	$ 126,552	$ 137,930	$ 126,657

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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-Publisher FASB
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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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