Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	$ 19,550	$ 15,141
Impaired loans, allowance for loan loss	$ 2,015	2,027
Percentage required stock to capital and surplus	6.00%
Impairment charges	$ 0	0
Consumer And Other Loans [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Period past due for loan appraisals	90 days
Impaired loans	$ 36	43
Impaired loans, allowance for loan loss	$ 36	$ 43
Minimum [Member] \| Impaired Loans [Member] \| Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	10.00%
Maximum [Member] \| Impaired Loans [Member] \| Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	50.00%
Investment In FRB Stock [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impairment charges	$ 0
FHLBNY [Member] \| Investment In FHLBNY Stock [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impairment charges	$ 0

Percentage Of Required Federal Reserve Bank Stock To Capital And Surplus

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Name Accounting Standards Codification
-Topic 320
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-Section 35
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Threshold period past due for financing receivable to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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