Loans, Troubled Debt Restructuring (Details)	3 Months Ended
Mar. 31, 2018 USD ($) Loan	Mar. 31, 2017 USD ($) Loan
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans \| Loan	0	2
Pre-Modification Recorded Balance	$ 0	$ 32,000
Post-Modification Recorded Balance	0	23,000
Troubled debt restructurings that subsequently defaulted within 12 months of the restructuring date	$ 0	$ 1,236,000
Commercial and industrial [Member]
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans \| Loan	0	0
Pre-Modification Recorded Balance	$ 0	$ 0
Post-Modification Recorded Balance	$ 0	$ 0
Commercial, secured by real estate [Member]
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans \| Loan	0	0
Pre-Modification Recorded Balance	$ 0	$ 0
Post-Modification Recorded Balance	$ 0	$ 0
Residential real estate [Member]
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans \| Loan	0	1
Pre-Modification Recorded Balance	$ 0	$ 18,000
Post-Modification Recorded Balance	$ 0	$ 9,000
Consumer [Member]
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans \| Loan	0	1
Pre-Modification Recorded Balance	$ 0	$ 14,000
Post-Modification Recorded Balance	$ 0	$ 14,000

-- None. No documentation exists for this element. --

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

+ Details

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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