Investments in Unconsolidated Companies (Schedule of Long-term Debt Maturities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Long-term Debt, Current Maturities	$ 547,732
2014	331,563
2015	679,945
2016	544,840
2017	566,611
Thereafter	1,768,944
Long-term Debt	4,439,635
Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt, Current Maturities	119,387
2014	51,757
2015	69,834
2016	14,948
2017	101,922
Thereafter	54,562
Long-term Debt	$ 412,410

Face Value of Debt, Maturity Total

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Carrying amount of long-term debt, net of unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

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-Publisher SEC

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-Number 210

-Section 02

-Paragraph 20

-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 02

-Paragraph 19

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 10

-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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

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