Regulatory Matters (Summary Of Actual Capital Amounts And Ratios) (Details) $ in Thousands	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Summit [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 (to risk weighted assets), Actual Amount	$ 252,581	$ 233,768
CET1 (to risk weighted assets), Actual Ratio	0.090	0.093
Tier I Capital (to risk weighted assets), Actual Amount	$ 286,501	$ 252,768
Tier I Capital (to risk weighted assets), Actual Ratio	0.102	0.100
Total Capital (to risk weighted assets), Actual Amount	$ 341,088	$ 305,309
Total Capital (to risk weighted assets), Actual Ratio	0.121	0.121
Tier I Capital (to average assets), Actual Amount	$ 286,501	$ 252,768
Tier I Capital (to average assets), Actual Ratio	0.084	0.086
Summit Community [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 (to risk weighted assets), Actual Amount	$ 313,549	$ 279,540
CET1 (to risk weighted assets), Actual Ratio	0.112	0.111
CET1 (to risk weighted assets), Minimum Required Capital, Amount	$ 195,968	$ 176,286
CET1 (to risk weighted assets), Minimum Required Capital, Ratio	7.00%	7.00%
CET1 (to risk weighted assets), Minimum Required To Be Well Capitalized, Amount	$ 181,970	$ 163,695
CET1 (to risk weighted assets), Minimum Required To Be Well Capitalized, Ratio	6.50%	6.50%
Tier I Capital (to risk weighted assets), Actual Amount	$ 313,549	$ 279,540
Tier I Capital (to risk weighted assets), Actual Ratio	0.112	0.111
Tier I Capital (to risk weighted assets), Minimum Required Capital, Amount	$ 237,961	$ 214,062
Tier I Capital (to risk weighted assets), Minimum Required Capital, Ratio	0.085	0.085
Tier I Capital (to risk weighted assets), Minimum Required To Be Well Capitalized, Amount	$ 223,964	$ 201,470
Tier I Capital (to risk weighted assets), Minimum Required To Be Well Capitalized, Ratio	0.080	0.080
Total Capital (to risk weighted assets), Actual Amount	$ 338,670	$ 302,716
Total Capital (to risk weighted assets), Actual Ratio	0.121	0.120
Total Capital (to risk weighted assets), Minimum Required Capital, Amount	$ 293,887	$ 264,877
Total Capital (to risk weighted assets), Minimum Required Capital, Ratio	0.105	0.105
Total Capital (to risk weighted assets), Minimum Required To Be Well Capitalized, Amount	$ 279,893	$ 252,263
Total Capital (to risk weighted assets), Minimum Required To Be Well Capitalized, Ratio	0.100	0.100
Tier I Capital (to average assets), Actual Amount	$ 313,549	$ 279,540
Tier I Capital (to average assets), Actual Ratio	0.092	0.095
Tier I Capital (to average assets), Minimum Required Capital, Amount	$ 136,326	$ 117,701
Tier I Capital (to average assets), Minimum Required Capital, Ratio	0.040	0.040
Tier I Capital (to average assets), Minimum Required To Be Well Capitalized, Amount	$ 170,407	$ 147,126
Tier I Capital (to average assets), Minimum Required To Be Well Capitalized, Ratio	0.050	0.050

Tier One Common Equity Required for Capital Adequacy to Risk Weighted Assets

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Amount of total capital as defined by regulatory framework.

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