Deposits (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Deposit Liabilities [Line Items]
CDARS Deposits	$ 1.1	$ 3.4
Time Deposits 100,000 Or More	47.4	54.2
Time Deposits 250,000 Or More	25.7	$ 31.7
Securities Available To Be Pledged As Collateral [Member]
Deposit Liabilities [Line Items]
Available-for-sale Securities Pledged as Collateral	129.4
Pledged Letters of Credit	30.3
Qualifying Collateral	14.4
Securities Pledged as Collateral [Member]
Deposit Liabilities [Line Items]
Qualifying collateral to secure deposits	$ 145.3

Certificates of deposit reciprocated in the Certificate of Deposit Account Registry Service Program.

No definition available.

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- Definition

Deposit Liabilities [Line Items]

+ References

No definition available.

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- Definition

As of the date of the latest financial statement presented, the notional amount of letters of credit which were available to be pledged as collateral for identified public deposits and trust fund.

+ References

No definition available.

+ Details

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- Definition

As of the balance sheet date, the total amount of excess collateral that the Company had for other pledging needs.

+ References

No definition available.

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- Definition

Certificates of deposit of $250,000 or more aggregated amount.

+ References

No definition available.

+ Details

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5086-111524

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- Definition

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

+ References

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- Definition

The aggregate amount of domestic and foreign time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph A
-Subparagraph 4

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