Fair Value Measurements (Details 2) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Assets - Beginning balance	$ 1,761	$ 1,832
Realized loss included in earnings - net mortgage banking derivatives	8	(71)
Assets - Ending balance	1,769	1,761
Liabilities - Beginning balance	10	55
Realized loss included in earnings - net mortgage banking derivatives	74	(45)
Liabilities - Ending balance	84	10
Investment Securities [Member]
Assets - Beginning balance	1,718	1,718
Assets - Ending balance	1,718	1,718
Mortgage Banking Derivatives [Member]
Assets - Beginning balance	43	114
Realized loss included in earnings - net mortgage banking derivatives	8	(71)
Assets - Ending balance	51	43
Liabilities - Beginning balance	10	55
Realized loss included in earnings - net mortgage banking derivatives	74	(45)
Liabilities - Ending balance	$ 84	$ 10

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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

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- Definition

Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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

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