Loans (Additional Information) (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($) loan	Jun. 30, 2016 USD ($) loan	Jun. 30, 2017 USD ($) loan	Jun. 30, 2016 USD ($) loan	Dec. 31, 2016 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans modified as troubled debt restructurings \| loan	1	0	2	0
Additional lending amount to customers whose loan terms has been modified in troubled debt restructuring	$ 0		$ 0		$ 0
Total allowance for loan losses for troubled debt restructuring loans	16,000		16,000		3,000
Increase in allowance for loan losses for troubled debt restructuring loans	8,000	$ 0	10,000	$ 0
Charge-offs due to troubled debt restructurings	$ 0	$ 0	$ 0	$ 0
Number of loans modified as troubled debt restructuring subsequently defaulted \| loan	0	0	0	0
Carrying amount of consumer mortgage loans secured by residential real estate properties	$ 137,000		$ 137,000		$ 202,000
Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in allowance for purchased loans	0	$ 0	11,000	$ 0
Reversal allowance for purchased loans	$ 56,000	$ 0	$ 56,000	$ 0

Allowance for Loan and Lease Losses, Reversal

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- Definition

Financing Receivables, Impaired, Trouble Debt Restructuring, Allowance For Loan and Lease Losses, Period Increase (Decrease)

+ References

No definition available.

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- Definition

Financing Receivables, Trouble Debt Restructuring, Allowance For Loan and Lease Losses

+ References

No definition available.

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- Definition

Troubled debt restructuring, additional lending amount

+ References

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of addition to allowance reserve for credit loss arising from purchase of loan and lease portfolios.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and 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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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL49126937-111524

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