Allowance for Credit Losses - Activity in ACL by Class of Loans and Leases (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Rollforward of the Allowance for Credit Losses
Balance at beginning of year	$ 160,393	$ 156,533	$ 156,533
Charge-offs	(6,498)	(5,763)
Recoveries	2,717	1,974
Provision	10,000	7,092
Balance at end of year	166,612	159,836	160,393
Commercial Lending
Rollforward of the Allowance for Credit Losses
Charge-offs	(1,459)		(4,015)
Commercial and Industrial
Rollforward of the Allowance for Credit Losses
Balance at beginning of year	16,332	14,956	14,956
Charge-offs	(1,459)	(909)	(3,615)
Recoveries	403	211
Provision	2,716	2,829
Balance at end of year	17,992	17,087	16,332
Commercial Real Estate
Rollforward of the Allowance for Credit Losses
Balance at beginning of year	40,624	43,944	43,944
Charge-offs			(400)
Recoveries	251
Provision	(1,505)	(418)
Balance at end of year	39,370	43,526	40,624
Construction
Rollforward of the Allowance for Credit Losses
Balance at beginning of year	8,570	10,392	10,392
Provision	941	2,049
Balance at end of year	9,511	12,441	8,570
Lease financing
Rollforward of the Allowance for Credit Losses
Balance at beginning of year	2,269	1,754	1,754
Provision	75	731
Balance at end of year	2,344	2,485	2,269
Residential mortgage
Rollforward of the Allowance for Credit Losses
Balance at beginning of year	39,230	36,880	36,880
Charge-offs	(14)
Recoveries	20	30
Provision	(4,876)	(120)
Balance at end of year	34,374	36,790	39,230
Residential mortgage \| Home Equity Line
Rollforward of the Allowance for Credit Losses
Charge-offs	(14)
Home Equity Line
Rollforward of the Allowance for Credit Losses
Balance at beginning of year	10,205	11,728	11,728
Charge-offs	(14)
Recoveries	64	44
Provision	15	(325)
Balance at end of year	10,270	11,447	10,205
Consumer
Rollforward of the Allowance for Credit Losses
Balance at beginning of year	43,163	36,879	36,879
Charge-offs	(5,025)	(4,854)	(18,002)
Recoveries	1,979	1,689
Provision	12,634	2,346
Balance at end of year	$ 52,751	$ 36,060	$ 43,163

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

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- Definition

Amount of increase in allowance for credit loss on financing receivable and net investment in leases from recovery.

+ References

No definition available.

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- 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.

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- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable and net investment in leases.

+ References

No definition available.

+ Details

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- 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

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