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Fair Value Measurements (Details Textual) (USD $) In Millions, unless otherwise specified			1 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Jun. 30, 2011 GOGAS [Member]	Sep. 30, 2013 GOGAS [Member]
Fair Value Measurements (Textual)
Stock option issued, exercise price			$ 5.0
Fair value of the GOGAS stock option
Investment options, expiration date			Apr. 09, 2015
Financial instrument included in other assets	$ 0.9	$ 0.7

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Financial instrument notes receivable included in other assets.

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Share-based compensation arrangement by share based payment award, options issued exercise price.

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- Definition

Expiration date of the option.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Footnote 5

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611



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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958



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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13495-108611



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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

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