Fair Value Measurements - Quantitative Information (Details)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Impaired loans
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling cost	8.00%	8.00%
Other real estate owned
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling cost	8.00%	6.00%
Minimum \| Impaired loans
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Market rate for borrower (discount rate)	3.25%
Maximum \| Impaired loans
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Market rate for borrower (discount rate)	9.80%

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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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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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