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Goodwill (Details Textual) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2011 | Jun. 30, 2009 | Dec. 31, 2011 | Dec. 31, 2009
Goodwill [Line Items] |  |  |  |
Goodwill impairment | $ 196,100,000 |  | $ 196,807,000 | $ 150,778,000
Goodwill (Textual) [Abstract] |  |  |  |
Amount of goodwill written off |  | 32,600,000 |  |
International Contract Operations [Member] |  |  |  |
Goodwill [Line Items] |  |  |  |
Goodwill impairment |  | $ 150,800,000 | $ 0 |

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- Definition Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill that is recorded in discontinued operations. + References No definition available. + Details
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- Definition Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 45 -Subparagraph e -Clause 5 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141R -Paragraph 72 -Subparagraph d -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 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 47 -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. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6905597&loc=d3e13816-109267 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 43 -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 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6905597&loc=d3e13854-109267 + Details
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