Loans - Troubled Debt Restructuring (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) contract	Dec. 31, 2015 USD ($) contract	Dec. 31, 2014 USD ($) contract
Loans modified as troubled debt restructurings included in impaired loan balances [Abstract]
Number of Contracts \| contract	8	8	5
Pre-Modification Outstanding Recorded Investment	$ 1,351	$ 1,097	$ 872
Post-Modification Outstanding Recorded Investment	$ 1,339	$ 1,082	$ 869
Number of loans that subsequently defaulted within 12 months of modification \| contract	0	0	0
Type of Modification, Rate	$ 0	$ 105	$ 0
Type of Modification, Structure	1,339	977	869
ALLL Impact	1	20	$ 1
Loans in the process of foreclosure	325
Residential OREO	$ 653	$ 643
Commercial
Loans modified as troubled debt restructurings included in impaired loan balances [Abstract]
Number of Contracts \| contract	2	0	0
Pre-Modification Outstanding Recorded Investment	$ 24	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	24	0	0
Type of Modification, Rate	0	0	0
Type of Modification, Structure	24	0	0
ALLL Impact	$ 0	$ 0	$ 0
Commercial real estate \| Real estate
Loans modified as troubled debt restructurings included in impaired loan balances [Abstract]
Number of Contracts \| contract	2	3	2
Pre-Modification Outstanding Recorded Investment	$ 1,005	$ 394	$ 743
Post-Modification Outstanding Recorded Investment	1,003	394	737
Type of Modification, Rate	0	0	0
Type of Modification, Structure	1,003	394	737
ALLL Impact	$ 0	$ 0	$ 0
Residential \| Real estate
Loans modified as troubled debt restructurings included in impaired loan balances [Abstract]
Number of Contracts \| contract	4	4	2
Pre-Modification Outstanding Recorded Investment	$ 322	$ 596	$ 121
Post-Modification Outstanding Recorded Investment	312	583	124
Type of Modification, Rate	0	0	0
Type of Modification, Structure	312	583	124
ALLL Impact	$ 1	$ 19	$ 1
Residential \| Home equity
Loans modified as troubled debt restructurings included in impaired loan balances [Abstract]
Number of Contracts \| contract	0	1	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 107	$ 8
Post-Modification Outstanding Recorded Investment	0	105	8
Type of Modification, Rate	0	105	0
Type of Modification, Structure	0	0	8
ALLL Impact	$ 0	$ 1	$ 0
Consumer
Loans modified as troubled debt restructurings included in impaired loan balances [Abstract]
Number of Contracts \| contract	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	0	0	0
Type of Modification, Rate	0	0	0
Type of Modification, Structure	0	0	0
ALLL Impact	$ 0	$ 0	$ 0

The impact of loan modifications on the loan balance at the end of the period.

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- Definition

Loan modifications due to interest adjustments.

+ References

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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

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

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

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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
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-Name Accounting Standards Codification
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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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