Allowance for Credit Losses - Loans on Nonaccrual Status and Loans Past Due 90 Days or More and Still Accruing (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($) loan
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	$ 66,291	$ 146,774
End of Period Nonaccrual	22,777	66,291
Nonaccrual With No Related Allowance	7,409	37,469
Interest income recognized on nonaccrual	1,132	$ 1,128
Number of modified loans \| loan		8
Modified loans		$ 28,800
Commercial Loans \| Commercial real estate
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	31,488	101,070
End of Period Nonaccrual	7,833	31,488
Nonaccrual With No Related Allowance	6,317	28,046
Interest income recognized on nonaccrual	625	158
Commercial Loans \| Commercial and industrial
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	15,239	16,985
End of Period Nonaccrual	335	15,239
Nonaccrual With No Related Allowance	0	5,707
Interest income recognized on nonaccrual	86	74
Commercial Loans \| Commercial construction
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	2,471	384
End of Period Nonaccrual	384	2,471
Nonaccrual With No Related Allowance	0	2,020
Interest income recognized on nonaccrual	0	(28)
Commercial Loans \| Business banking
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	9,641	17,122
End of Period Nonaccrual	6,445	9,641
Nonaccrual With No Related Allowance	1,092	1,696
Interest income recognized on nonaccrual	242	427
Consumer Loans \| Consumer real estate
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	7,294	11,117
End of Period Nonaccrual	7,373	7,294
Nonaccrual With No Related Allowance	0	0
Interest income recognized on nonaccrual	178	496
Consumer Loans \| Other Consumer
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	158	96
End of Period Nonaccrual	407	158
Nonaccrual With No Related Allowance	0	0
Interest income recognized on nonaccrual	$ 1	$ 1

Financing Receivable, Non-TDR Modifications, Number Of Contracts

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Financing Receivable, Non-TDR Restructuring, Postmodification

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No definition available.

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

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Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 50
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-Subparagraph (a)
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-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
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-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
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