Loans - Allowance for Credit Losses by Portfolio Type (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Allowance for loan losses
Balance, beginning of period	$ 77,362	$ 56,077	$ 65,917	$ 47,547
Provision (benefit) for credit losses	3,600	3,750	10,560	12,450
Loans charged off	(3,099)	(300)	(4,019)	(2,412)
Recoveries	803	151	952	2,093
Balance, end of period	78,666	59,678	78,666	59,678
Impact of adopting ASC 326
Allowance for loan losses
Balance, beginning of period			5,256
Commercial and Industrial
Allowance for loan losses
Balance, beginning of period	33,197	33,305	40,785	31,622
Provision (benefit) for credit losses	4,252	2,394	10,941	4,304
Loans charged off	(2,963)	(223)	(3,751)	(2,173)
Recoveries	155	112	249	1,835
Balance, end of period	34,641	35,588	34,641	35,588
Commercial and Industrial \| Impact of adopting ASC 326
Allowance for loan losses
Balance, beginning of period			(13,583)
Commercial Real Estate
Allowance for loan losses
Balance, beginning of period	21,598	18,351	19,754	13,198
Provision (benefit) for credit losses	1,495	1,213	(531)	6,365
Loans charged off	0	0	0	0
Recoveries	9	2	12	3
Balance, end of period	23,102	19,566	23,102	19,566
Commercial Real Estate \| Impact of adopting ASC 326
Allowance for loan losses
Balance, beginning of period			3,867
Residential real estate
Allowance for loan losses
Balance, beginning of period	14,959	2,418	2,963	836
Provision (benefit) for credit losses	(2,429)	222	(710)	1,707
Loans charged off	0	(24)	0	(122)
Recoveries	627	1	648	196
Balance, end of period	13,157	2,617	13,157	2,617
Residential real estate \| Impact of adopting ASC 326
Allowance for loan losses
Balance, beginning of period			10,256
Public finance
Allowance for loan losses
Balance, beginning of period	5,506	1,538	1,664	1,544
Provision (benefit) for credit losses	135	(108)	87	(114)
Loans charged off	0	0	0	0
Recoveries	0	0	0	0
Balance, end of period	5,641	1,430	5,641	1,430
Public finance \| Impact of adopting ASC 326
Allowance for loan losses
Balance, beginning of period			3,890
Consumer
Allowance for loan losses
Balance, beginning of period	854	318	352	235
Provision (benefit) for credit losses	(28)	32	326	156
Loans charged off	(136)	(53)	(268)	(117)
Recoveries	12	36	43	59
Balance, end of period	702	333	702	333
Consumer \| Impact of adopting ASC 326
Allowance for loan losses
Balance, beginning of period			249
Other
Allowance for loan losses
Balance, beginning of period	1,248	147	399	112
Provision (benefit) for credit losses	175	(3)	447	32
Loans charged off	0	0	0	0
Recoveries	0	0	0	0
Balance, end of period	$ 1,423	$ 144	1,423	$ 144
Other \| Impact of adopting ASC 326
Allowance for loan losses
Balance, beginning of period			$ 577

Financing Receivable, Credit Loss, Expense (Reversal), Excluding For Unfunded Commitments

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- Definition

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

+ References

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- Definition

Amount of increase in allowance for credit loss on financing receivable from recovery.

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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 writeoff of financing receivable, charged against allowance for credit loss.

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