Investments in Unconsolidated Companies (Schedule of Long-term Debt Maturities) (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Schedule of Equity Method Investments [Line Items]
2019	$ 45,515
2020	3,883
2021	262,463
2022	603,611
2023	283,817
Thereafter	1,485,361
Long-term Debt	2,684,650
Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
2019	3,955
2020	0
2021	61,094
2022	122
2023	126
Thereafter	36,867
Long-term Debt	$ 102,164

Face Value of Debt, Maturity Total

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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-Publisher FASB
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-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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