Off-Balance Sheet Credit Risk (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value of securities accepted as collateral permitted to sell or repledge	$ 1,200,000,000	$ 1,200,000
Fair value of collateral securities sold or repledged	39,200,000	263,800,000
Outstanding commitments to originate loans	122,800,000	66,800,000
Letters of credit outstanding	10,400,000	5,100,000
Unused lines of Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused lines of credit to commercial and consumer borrowers	$ 358,100,000	$ 282,000,000

Outstanding Commitments to Originate Loans

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Unused Lines of Credit to Commercial and Consumer Borrowers

+ References

No definition available.

+ Details

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- Definition

Fair value as of the balance sheet date of customer securities accepted as collateral by the entity that it is permitted by contract or custom to sell or re-pledge to counterparties as collateral.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7523297&loc=SL6224234-111729

+ Details

Name:	us-gaap_CustomerSecuritiesForWhichEntityHasRightToSellOrRepledgeFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value as of the balance sheet date of customer securities accepted as collateral by the entity that it has sold or re-pledged to counterparties as collateral.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=7523297&loc=SL6224234-111729

+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Details

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