Securities (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Securities [Abstract]
Private mortgage-backed security fair value	$ 490
Investment securities, pledged as collateral for public deposits	213,825		$ 147,009
Proceeds from sales of securities	45,601	$ 8
Net realized gain loss of investment securities	(235)	$ 3
Federal Home Loan Bank stock and Federal Reserve Bank stock, cost	30,198		19,826
Federal Home Loan Bank Stock, cost	18,507		12,588
Federal Reserve Bank, cost	$ 11,691		$ 7,238

Private mortgage-backed security fair value.

No definition available.

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- Definition

The proceeds during the period from the sale of all securities.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

+ Details

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809

+ Details

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- Definition

Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

+ References

No definition available.

+ Details

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- Definition

Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

+ Details

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- Definition

This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity.

+ References

No definition available.

+ Details

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