Fair Value Disclosures (Estimated Fair Values and Carrying Amounts of Assets and Liabilities) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents, carrying value	$ 567,599,000	$ 178,810,000
Cash and cash equivalents, fair value	567,599,000	178,810,000
Restricted cash, carrying value	129,547,000	135,731,000
Restricted cash, fair value	129,547,000	135,731,000
Foreign Currency Swaps, Carrying Value, Net	0	10,479,000
Foreign Currency Swaps, Fair Value, Net	0	10,479,000
Debt and other obligations, carrying amount	12,171,142,000	12,149,959,000
Debt and other obligations, fair value	12,660,013,000	12,555,143,000
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents, carrying value	1
Restricted cash, carrying value	1
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Issuance Date	2
Debt and other obligations, carrying amount	2
Securitized Debt [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt and other obligations, carrying amount	$ 3,345,805,000	$ 4,007,123,000