Loans (Narrative) (Details) $ in Millions	6 Months Ended
Jun. 30, 2015 USD ($) contract	Dec. 31, 2014 USD ($)
Financing Receivable, Recorded Investment [Line Items]
Loans to related parties	$ 10.1	$ 13.2
Loans and Leases Receivable, Related Parties, Additions	0.0
Repayments on related party loans	$ 3.1
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| contract	0
Loans Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 1,220.0	1,080.0
Federal Reserve Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 47.5	$ 46.0

Federal Reserve Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at 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 210.9-03.7(e))

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- Definition

Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

+ References

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- Definition

Reflects the amount of collections received from related parties to reduce the carrying amounts of loans and leases receivable due from them.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(e))

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