Loans and Loans Held for Sale - Restructured Loans by Type of Concession (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	40	53
Pre-Modification Outstanding Recorded Investment	$ 25,295	$ 32,446
Post-Modification Outstanding Recorded Investment	22,650	32,206
Total Difference in Recorded Investment	$ (2,645)	$ (240)
Payment/Principal deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	3	4
Pre-Modification Outstanding Recorded Investment	$ 5,415	$ 24,767
Post-Modification Outstanding Recorded Investment	4,842	24,309
Total Difference in Recorded Investment	$ (573)	$ (458)
Maturity date extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	5
Pre-Modification Outstanding Recorded Investment	$ 14,120
Post-Modification Outstanding Recorded Investment	12,099
Total Difference in Recorded Investment	$ (2,021)
Maturity date extension and interest rate reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1	2
Pre-Modification Outstanding Recorded Investment	$ 3,735	$ 4,902
Post-Modification Outstanding Recorded Investment	3,735	4,280
Total Difference in Recorded Investment	$ 0	$ (622)
Payment delay and below market interest rate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	2
Pre-Modification Outstanding Recorded Investment	$ 362
Post-Modification Outstanding Recorded Investment	354
Total Difference in Recorded Investment	$ (8)
Consumer bankruptcy
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	23	36
Pre-Modification Outstanding Recorded Investment	$ 993	$ 1,068
Post-Modification Outstanding Recorded Investment	960	977
Total Difference in Recorded Investment	$ (33)	$ (91)
Maturity date extension and reduction in payment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	6
Pre-Modification Outstanding Recorded Investment	$ 670
Post-Modification Outstanding Recorded Investment	660
Total Difference in Recorded Investment	$ (10)
Principal deferral and maturity date extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		7
Pre-Modification Outstanding Recorded Investment		$ 950
Post-Modification Outstanding Recorded Investment		933
Total Difference in Recorded Investment		$ (17)
Below market interest rate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		2
Pre-Modification Outstanding Recorded Investment		$ 569
Post-Modification Outstanding Recorded Investment		1,519
Total Difference in Recorded Investment		$ 950
Interest rate reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		2
Pre-Modification Outstanding Recorded Investment		$ 190
Post-Modification Outstanding Recorded Investment		188
Total Difference in Recorded Investment		$ (2)
Commercial real estate | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1	7
Pre-Modification Outstanding Recorded Investment	$ 5,292	$ 24,672
Post-Modification Outstanding Recorded Investment	4,791	25,159
Total Difference in Recorded Investment	$ (501)	$ 486
Commercial real estate | Payment/Principal deferral | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1	3
Pre-Modification Outstanding Recorded Investment	$ 5,292	$ 23,517
Post-Modification Outstanding Recorded Investment	4,791	23,059
Total Difference in Recorded Investment	$ (501)	$ (458)
Commercial real estate | Maturity date extension and interest rate reduction | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		1
Pre-Modification Outstanding Recorded Investment		$ 150
Post-Modification Outstanding Recorded Investment		145
Total Difference in Recorded Investment		$ (6)
Commercial real estate | Principal deferral and maturity date extension | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		1
Pre-Modification Outstanding Recorded Investment		$ 436
Post-Modification Outstanding Recorded Investment		436
Total Difference in Recorded Investment		$ 0
Commercial real estate | Below market interest rate | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		2
Pre-Modification Outstanding Recorded Investment		$ 569
Post-Modification Outstanding Recorded Investment		1,519
Total Difference in Recorded Investment		$ 950
Business banking | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 333
Post-Modification Outstanding Recorded Investment	165
Total Difference in Recorded Investment	$ (168)
Business banking | Maturity date extension | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 333
Post-Modification Outstanding Recorded Investment	165
Total Difference in Recorded Investment	$ (168)
Commercial and industrial | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	5	3
Pre-Modification Outstanding Recorded Investment	$ 15,385	$ 6,294
Post-Modification Outstanding Recorded Investment	13,716	5,661
Total Difference in Recorded Investment	$ (1,669)	$ (633)
Commercial and industrial | Payment/Principal deferral | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1	1
Pre-Modification Outstanding Recorded Investment	$ 93	$ 1,250
Post-Modification Outstanding Recorded Investment	22	1,250
Total Difference in Recorded Investment	$ (71)	$ 0
Commercial and industrial | Maturity date extension | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 11,195
Post-Modification Outstanding Recorded Investment	9,605
Total Difference in Recorded Investment	$ (1,590)
Commercial and industrial | Maturity date extension and interest rate reduction | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1	1
Pre-Modification Outstanding Recorded Investment	$ 3,735	$ 4,751
Post-Modification Outstanding Recorded Investment	3,735	4,136
Total Difference in Recorded Investment	$ 0	$ (616)
Commercial and industrial | Payment delay and below market interest rate | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	2
Pre-Modification Outstanding Recorded Investment	$ 362
Post-Modification Outstanding Recorded Investment	354
Total Difference in Recorded Investment	$ (8)
Commercial and industrial | Principal deferral and maturity date extension | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		1
Pre-Modification Outstanding Recorded Investment		$ 292
Post-Modification Outstanding Recorded Investment		275
Total Difference in Recorded Investment		$ (17)
Commercial construction | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	3
Pre-Modification Outstanding Recorded Investment	$ 2,592
Post-Modification Outstanding Recorded Investment	2,329
Total Difference in Recorded Investment	$ (263)
Commercial construction | Maturity date extension | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	3
Pre-Modification Outstanding Recorded Investment	$ 2,592
Post-Modification Outstanding Recorded Investment	2,329
Total Difference in Recorded Investment	$ (263)
Consumer real estate | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	29
Pre-Modification Outstanding Recorded Investment	$ 1,688
Post-Modification Outstanding Recorded Investment	1,645
Total Difference in Recorded Investment	$ (43)
Consumer real estate | Payment/Principal deferral | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 30
Post-Modification Outstanding Recorded Investment	29
Total Difference in Recorded Investment	$ (1)
Consumer real estate | Consumer bankruptcy | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	22
Pre-Modification Outstanding Recorded Investment	$ 988
Post-Modification Outstanding Recorded Investment	956
Total Difference in Recorded Investment	$ (32)
Consumer real estate | Maturity date extension and reduction in payment | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	6
Pre-Modification Outstanding Recorded Investment	$ 670
Post-Modification Outstanding Recorded Investment	660
Total Difference in Recorded Investment	$ (10)
Other consumer | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 5
Post-Modification Outstanding Recorded Investment	4
Total Difference in Recorded Investment	$ (1)
Other consumer | Consumer bankruptcy | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 5
Post-Modification Outstanding Recorded Investment	4
Total Difference in Recorded Investment	$ (1)
Residential mortgage | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		6
Pre-Modification Outstanding Recorded Investment		$ 348
Post-Modification Outstanding Recorded Investment		340
Total Difference in Recorded Investment		$ (9)
Residential mortgage | Consumer bankruptcy | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		3
Pre-Modification Outstanding Recorded Investment		$ 165
Post-Modification Outstanding Recorded Investment		157
Total Difference in Recorded Investment		$ (9)
Residential mortgage | Principal deferral and maturity date extension | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		3
Pre-Modification Outstanding Recorded Investment		$ 183
Post-Modification Outstanding Recorded Investment		183
Total Difference in Recorded Investment		$ 0
Home equity | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		33
Pre-Modification Outstanding Recorded Investment		$ 1,116
Post-Modification Outstanding Recorded Investment		1,037
Total Difference in Recorded Investment		$ (79)
Home equity | Consumer bankruptcy | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		29
Pre-Modification Outstanding Recorded Investment		$ 886
Post-Modification Outstanding Recorded Investment		810
Total Difference in Recorded Investment		$ (77)
Home equity | Principal deferral and maturity date extension | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		2
Pre-Modification Outstanding Recorded Investment		$ 39
Post-Modification Outstanding Recorded Investment		39
Total Difference in Recorded Investment		$ 0
Home equity | Interest rate reduction | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		2
Pre-Modification Outstanding Recorded Investment		$ 190
Post-Modification Outstanding Recorded Investment		188
Total Difference in Recorded Investment		$ (2)
Installment and other consumer | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		4
Pre-Modification Outstanding Recorded Investment		$ 16
Post-Modification Outstanding Recorded Investment		11
Total Difference in Recorded Investment		$ (5)
Installment and other consumer | Consumer bankruptcy | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans | loan		4
Pre-Modification Outstanding Recorded Investment		$ 16
Post-Modification Outstanding Recorded Investment		11
Total Difference in Recorded Investment		$ (5)