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Fair Value Accounting (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Securities available for sale:
US government agencies	$ 8,653	$ 6,159
SBA securities	4,063	1,437
State and political subdivisions	11,396	20,474
Mortgage-backed securities	43,491	36,410
Mortgage loans held for sale	11,790	7,801
Mortgage loan interest rate lock commitments	196	256
Total assets measured at fair value on a recurring basis	79,589	72,537
Liabilities
MBS forward sales commitments	28	3
Total liabilities measured at fair value on a recurring basis	28	3
Level 1 [Member]
Securities available for sale:
US government agencies
SBA securities
State and political subdivisions
Mortgage-backed securities
Mortgage loans held for sale
Mortgage loan interest rate lock commitments
Total assets measured at fair value on a recurring basis
Liabilities
MBS forward sales commitments
Total liabilities measured at fair value on a recurring basis
Level 2 [Member]
Securities available for sale:
US government agencies	8,653	6,159
SBA securities	4,063	1,437
State and political subdivisions	11,396	20,474
Mortgage-backed securities	43,491	36,410
Mortgage loans held for sale	11,790	7,801
Mortgage loan interest rate lock commitments	196	256
Total assets measured at fair value on a recurring basis	79,589	72,537
Liabilities
MBS forward sales commitments	28	3
Total liabilities measured at fair value on a recurring basis	28	3
Level 3 [Member]
Securities available for sale:
US government agencies
SBA securities
State and political subdivisions
Mortgage-backed securities
Mortgage loans held for sale
Mortgage loan interest rate lock commitments
Total assets measured at fair value on a recurring basis
Liabilities
MBS forward sales commitments
Total liabilities measured at fair value on a recurring basis

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ 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 (a)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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Fair value of obligations incurred from short sales.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 35
-Paragraph 1
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-SubTopic 10
-Section 50
-Paragraph 2
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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

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