Fair Value Measurements (Details 1) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012
Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
Balance at December 31, 2011	$ 6,751
Total gains (losses) realized (unrealized):
Included in earnings
Included in other comprehensive income	(45)
Net purchases, sales & distributions
Net transfers in (out of) Level 3
Balance at September 30, 2012	6,706
Change in net unrealized gains relating to assets still held at reporting date	$ (45)

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- Definition

Amount of unrealized gains and losses, net, (not included earnings), during the period from certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments) and which the entity has or had based its calculation of fair market value on unobservable inputs (Level 3).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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- Definition

Amount of gain (loss) recognized in earnings, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

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- Definition

Amount of gain (loss) recognized in other comprehensive income, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1a)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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- Definition

Amount of purchases, sales, issues, and settlements (net) for financial instruments classified in shareholders' equity measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

No definition available.

+ Details

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- Definition

Amount of transfers out of financial instruments classified in shareholders' equity measured at fair value and categorized within level 3 of the fair value hierarchy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

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- Definition

Amount of financial instruments classified in shareholders' equity, measured at fair value using significant unobservable inputs (Level 3), which is required for reconciliation purposes of beginning and ending balances.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

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