Fair Value Measurements - Additional Quantitative Information (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Quantitative Information about Level 3 Fair Value Measurements
Impaired loans	$ 36,831	$ 36,717
Non-recurring basis
Quantitative Information about Level 3 Fair Value Measurements
Impaired loans	3,396	3,885
Non-recurring basis \| Level 3
Quantitative Information about Level 3 Fair Value Measurements
Impaired loans	3,396	3,885
Non-recurring basis \| Level 3 \| Appraisal of collateral \| Impaired loans
Quantitative Information about Level 3 Fair Value Measurements
Impaired loans	$ 3,396	$ 3,885
Non-recurring basis \| Level 3 \| Appraisal of collateral \| Impaired loans \| Minimum
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)	(20.30%)	(19.20%)
Non-recurring basis \| Level 3 \| Appraisal of collateral \| Impaired loans \| Maximum
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)	(100.00%)	(100.00%)
Non-recurring basis \| Level 3 \| Appraisal of collateral \| Impaired loans \| Weighted Average
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)	(36.40%)	(38.40%)
Non-recurring basis \| Level 3 \| Appraisal of collateral \| OREO
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)	(100.00%)	(100.00%)
Non-recurring basis \| Level 3 \| Appraisal of collateral \| OREO \| Weighted Average
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)	(100.00%)	(100.00%)

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- Definition

Percentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.

+ 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)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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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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