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Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Federal Reserve Bank Of New York [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Reserve requirement	$ 6.4		$ 5.5
Subordinated Notes Due April 15, 2030 [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 2 capital	39.3
Preferred Equity [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 capital	$ 17.3
Fully Phased-in [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital Conservation Buffer	2.50%
Phase-in Schedule [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital Conservation Buffer	0.625%
Minimum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 capital, For Capital Adequacy Purposes, Ratio	4.50%
Tier 1 capital, For Capital Adequacy Purposes, Ratio	6.00%
Total risk-based capital, For Capital Adequacy Purposes, Ratio	8.00%
Minimum [Member] | Fully Phased-in [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 capital, For Capital Adequacy Purposes, Ratio	7.00%
Tier 1 capital, For Capital Adequacy Purposes, Ratio	8.50%
Total risk-based capital, For Capital Adequacy Purposes, Ratio	10.50%
Tier 1 leverage, For Capital Adequacy Purposes, Ratio	4.00%
Community Bank Leverage Ratio [Member] | Bank Maintains More Than Community Bank Leverage Ratio Percent [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of adequate CBLR to be maintained for qualifying and not qualifying community banking organizations		9.00%
Community Bank Leverage Ratio [Member] | Bank Does Not Maintain More Than Community Bank Leverage Ratio Percent [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of adequate CBLR to be maintained for qualifying and not qualifying community banking organizations		9.00%
Community Bank Leverage Ratio [Member] | Minimum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of community bank leverage ratio	8.00%
Community Bank Leverage Ratio [Member] | Maximum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of community bank leverage ratio	10.00%

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The amount of excess Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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