Loans and Allowance for Credit Losses for Loans - Summary of Activity in Allowance for Loan Losses (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	$ 446,080	$ 458,655	$ 458,655
Loans charged-off	(24,900)	(32,573)
Charged-off loans recovered	1,345	2,205
Net (charge-offs) recoveries	(23,555)	(30,368)
Provision for loan losses	46,723	9,979
Ending balance	469,248	436,898	446,080
Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses:
Beginning balance		(1,368)	(1,368)
Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for loan losses:
Beginning balance		457,287	457,287
Commercial and industrial
Allowance for loan losses:
Beginning balance	133,359	139,941	139,941
Loans charged-off	(14,293)	(26,047)
Charged-off loans recovered	682	1,399
Net (charge-offs) recoveries	(13,611)	(24,648)
Provision for loan losses	18,845	13,438
Ending balance	138,593	127,992	133,359
Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses:
Beginning balance		(739)	(739)
Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for loan losses:
Beginning balance		139,202	139,202
Commercial Real Estate
Allowance for loan losses:
Beginning balance	249,598	259,408	259,408
Loans charged-off	(8,798)	(5,698)
Charged-off loans recovered	241	24
Net (charge-offs) recoveries	(8,557)	(5,674)
Provision for loan losses	24,806	(9,813)
Ending balance	265,847	243,332	249,598
Commercial Real Estate \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses:
Beginning balance		(589)	(589)
Commercial Real Estate \| Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for loan losses:
Beginning balance		258,819	258,819
Residential Mortgage
Allowance for loan losses:
Beginning balance	42,957	39,020	39,020
Loans charged-off	0	0
Charged-off loans recovered	25	21
Net (charge-offs) recoveries	25	21
Provision for loan losses	1,395	2,679
Ending balance	44,377	41,708	42,957
Residential Mortgage \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses:
Beginning balance		(12)	(12)
Residential Mortgage \| Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for loan losses:
Beginning balance		39,008	39,008
Consumer loans
Allowance for loan losses:
Beginning balance	20,166	20,286	20,286
Loans charged-off	(1,809)	(828)
Charged-off loans recovered	397	761
Net (charge-offs) recoveries	(1,412)	(67)
Provision for loan losses	1,677	3,675
Ending balance	$ 20,431	23,866	20,166
Consumer loans \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses:
Beginning balance		(28)	(28)
Consumer loans \| Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for loan losses:
Beginning balance		$ 20,258	$ 20,258

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoffAfterRecovery
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. 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
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	srt_CumulativeEffectPeriodOfAdoptionAxis=srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CumulativeEffectPeriodOfAdoptionAxis=srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: