Commitments and Contingencies (ACL on Unfunded Commitments Rollforward) (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jan. 01, 2020
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	$ 2,333,000	$ 2,155,000	$ 2,382,000	$ 293,000
Adoption of Topic 326					$ 1,483,000
Provision	0	25,000	(49,000)	404,000
Ending balance	2,333,000	2,180,000	2,333,000	2,180,000
Commercial Real Estate
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	1,214,000	887,000	907,000	136,000
Adoption of Topic 326					817,000
Provision	4,000	(30,000)	311,000	(96,000)
Ending balance	1,218,000	857,000	1,218,000	857,000
Commercial & Industrial
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	1,045,000	1,207,000	1,402,000	144,000
Adoption of Topic 326					626,000
Provision	(8,000)	60,000	(365,000)	497,000
Ending balance	1,037,000	1,267,000	1,037,000	1,267,000
Total Commercial
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	2,259,000	2,094,000	2,309,000	280,000
Adoption of Topic 326					1,443,000
Provision	(4,000)	30,000	(54,000)	401,000
Ending balance	2,255,000	2,124,000	2,255,000	2,124,000
Residential Real Estate
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	56,000	42,000	54,000	6,000
Adoption of Topic 326					34,000
Provision	4,000	(5,000)	6,000	(3,000)
Ending balance	60,000	37,000	60,000	37,000
Home Equity
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	0	0	0	0
Adoption of Topic 326					0
Provision	0	0	0	0
Ending balance	0	0	0	0
Other
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	18,000	19,000	19,000	7,000
Adoption of Topic 326					6,000
Provision	0	0	(1,000)	6,000
Ending balance	18,000	19,000	18,000	19,000
Total Consumer
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	18,000	19,000	19,000	7,000
Adoption of Topic 326					$ 6,000
Provision	0	0	(1,000)	6,000
Ending balance	$ 18,000	$ 19,000	$ 18,000	$ 19,000

Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121611286&loc=d3e11927-110247

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82919202-210446

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

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The impact of the adoption of Topic 326 on the allowance for credit losses on unfunded commitments, effective 1/1/20.

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