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Loans and Loans Held for Sale - Summary of Restructured Loans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans	$ 427	$ 1,377	$ 1,930	$ 8,159
Commercial real estate | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans	0	0	0	0
Commercial and industrial | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans	0	0	0	6,229
Commercial construction | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans	0	0	0	0
Business banking | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans	0	1,130	0	1,210
Consumer real estate | Consumer Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans	425	247	1,927	720
Other Consumer | Consumer Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans	$ 2	$ 0	3	$ 0
Total TDRs
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			13,348		$ 31,695
Total TDRs | Commercial real estate | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			16		1,697
Total TDRs | Commercial and industrial | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			690		15,637
Total TDRs | Commercial construction | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			2,174		4,277
Total TDRs | Business banking | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			2,005		2,554
Total TDRs | Consumer real estate | Consumer Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			8,458		7,527
Total TDRs | Other Consumer | Consumer Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			5		3
Accruing TDRs
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			9,338		9,921
Accruing TDRs | Commercial real estate | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			0		0
Accruing TDRs | Commercial and industrial | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			690		748
Accruing TDRs | Commercial construction | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			1,694		2,190
Accruing TDRs | Business banking | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			680		858
Accruing TDRs | Consumer real estate | Consumer Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			6,269		6,122
Accruing TDRs | Other Consumer | Consumer Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			5		3
Nonaccruing TDRs
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			4,010		21,774
Nonaccruing TDRs | Commercial real estate | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			16		1,697
Nonaccruing TDRs | Commercial and industrial | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			0		14,889
Nonaccruing TDRs | Commercial construction | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			480		2,087
Nonaccruing TDRs | Business banking | Commercial Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			1,325		1,696
Nonaccruing TDRs | Consumer real estate | Consumer Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			2,189		1,405
Nonaccruing TDRs | Other Consumer | Consumer Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured loans			$ 0		$ 0

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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