Intangible Assets (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Intangible Assets (Textual) [Abstract]
Expected amortization expense for 2013	$ 0.8
Expected amortization expense for 2014	0.8
Expected amortization expense for 2015	0.8
Expected amortization expense for 2016	0.8
Expected amortization expense for 2017	0.8
Thereafter	0.8
Subsequent impairment of the underlying assets	$ 0

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Amount of amortization expense expected to be recognized in the next rolling twelve months following the latest balance sheet presented for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense expected to be recognized after the fifth rolling twelve months following the latest balance sheet presented for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense expected to be recognized in the fifth rolling twelve months following the latest balance sheet presented for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense expected to be recognized in the fourth rolling twelve months following the latest balance sheet presented for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense expected to be recognized in the third rolling twelve months following the latest balance sheet presented for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense expected to be recognized in the second rolling twelve months following the latest balance sheet presented for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

+ Details

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16373-109275

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 46

-Subparagraph b

-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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