Borrowings (Advances from FHLB) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Balance outstanding at end of year	$ 135,000	$ 189,000
Average balance outstanding	124,301	125,047
Maximum outstanding at any month-end	$ 185,000	$ 189,000
Average interest rate during the year	1.15%	0.91%
Average interest rate at end of year	1.36%	0.91%

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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Balance Type:	credit
Period Type:	instant

- References

No definition available.

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- Definition

The calculated average balance outstanding for the year for all Federal Home Loan Bank advances as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

+ References

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- Definition

The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date.

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- Definition

The maximum balance outstanding at any month end during the period as of the Balance Sheet date.

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