Loans (Additional Information) (Details)	3 Months Ended
Mar. 31, 2017 USD ($) loan	Mar. 31, 2016 USD ($) loan	Dec. 31, 2016 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans modified as troubled debt restructurings \| loan	1	0
Additional lending amount to customers whose loan terms has been modified in troubled debt restructuring	$ 0		$ 0
Increase in allowance for loan losses for troubled debt restructuring loans	2,000	$ 0
Charge-offs due to troubled debt restructurings	$ 0	$ 0
Number of loans modified as troubled debt restructuring subsequently defaulted \| loan	0	0
Carrying amount of consumer mortgage loans secured by residential real estate properties	$ 168,000		$ 202,000
Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in allowance for purchased loans	11,000	$ 0
Loan losses reversed	$ 0	$ 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

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=66008989&loc=d3e5212-111524

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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-Paragraph 33
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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

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

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

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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
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-SubTopic 10
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