Preferred Stock and Common Stock Warrants-Common Stock Warrants (Details) (Common Stock [Member], USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended
Dec. 19, 2008	Dec. 31, 2012
Common Stock [Member]
Class of Warrant or Right [Line Items]
Exercise duration of warrants		10 years
Exercise price of warrants		16.20
Fair value assumptions, weighted average expected term		10 years
Fair value assumptions, risk free interest rate		3.10%
Fair value assumptions, expected volatility rate		47.30%
Fair value assumptions, expected dividend rate		5.00%
Estimated fair value	$ 3.9	$ 3.0
Aggregate investment by U.S. Treasury	$ 35.0

Class of Warrant or Right, Exercise Duration of Warrants or Rights

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- Definition

Class of Warrant or Right, Fair Value Assumptions, Expected Dividend Rate

+ References

No definition available.

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- Definition

Class of Warrant or Right, Fair Value Assumptions, Expected Volatility Rate

+ References

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- Definition

Class of Warrant or Right, Fair Value Assumptions, Risk Free Interest Rate

+ References

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- Definition

Class of Warrant or Right, Fair Value Assumptions, Weighted Average Expected Term

+ References

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- Definition

Preferred Stock and Class of Warrant or Right, Cash Received on Issuance

+ References

No definition available.

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- Definition

The exercise price of each class of warrants or rights outstanding.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i)(4))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Subparagraph 4

-Article 4

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 98-5

-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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Article 4

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 00-27

-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.

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