Borrowings - Collateral Agreement With Federal Home Loans Bank (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Debt Instrument [Line Items]
Interest Rate, Minimum	0.86%
Interest Rate, Maximum	6.81%
Total available remaining borrowing capacity from FHLB	217,275
Minimum
Debt Instrument [Line Items]
Required value of assets pledged as collateral as a percentage to outstanding advances	155.00%

Federal Home Loan Bank, Advances, Required Collateral, Percent

No definition available.

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- Details

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Subparagraph b

-Article 5

+ Details

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- Definition

Discloses the lowest interest rate applicable to any of the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 17, 37

-IssueDate 2006-05-01

-Chapter 15

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

Discloses the highest interest rate applicable to any of the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

+ Details

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