Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of long-term debt, after 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.

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Fair Value Measurements - Carrying Amounts and Fair Values (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 85,909	$ 51,777	$ 161,558	$ 199,644
Restricted cash	71,708	23,525
Current maturities of long-term debt	(31,676)	0
Long-term debt (c)	(1,030,205)	(830,554)
Carrying Amount \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	85,909
Cash and cash equivalents		51,777
Restricted cash	71,708	23,525
Current maturities of long-term debt	(31,676)	0
Long-term debt (c)	(1,030,205)	(830,554)
Carrying Amount \| Fair Value, Measurements, Recurring \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps, assets	11,225
Interest rate swaps, liabilities		(18,244)
Carrying Amount \| Fair Value, Measurements, Recurring \| Foreign currency exchange contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign Currency Contracts, Liability		(1,625)
Foreign Currency Contracts, Asset	464
Carrying Amount \| Fair Value, Measurements, Recurring \| Foreign currency option contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign Currency Contracts, Asset	391	3,964
Fair Value \| Level 1 \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	85,909	51,777
Restricted cash	71,708	23,525
Current maturities of long-term debt	0	0
Long-term debt (c)	0	0
Fair Value \| Level 1 \| Fair Value, Measurements, Recurring \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps, assets	0
Interest rate swaps, liabilities		0
Fair Value \| Level 1 \| Fair Value, Measurements, Recurring \| Foreign currency exchange contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign Currency Contracts, Liability		0
Foreign Currency Contracts, Asset	0
Fair Value \| Level 1 \| Fair Value, Measurements, Recurring \| Foreign currency option contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign Currency Contracts, Asset	0	0
Fair Value \| Level 2 \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Restricted cash	0	0
Current maturities of long-term debt	(31,984)	0
Long-term debt (c)	(1,030,708)	(830,203)
Fair Value \| Level 2 \| Fair Value, Measurements, Recurring \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps, assets	11,225
Interest rate swaps, liabilities		(18,244)
Fair Value \| Level 2 \| Fair Value, Measurements, Recurring \| Foreign currency exchange contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign Currency Contracts, Liability		(1,625)
Foreign Currency Contracts, Asset	464
Fair Value \| Level 2 \| Fair Value, Measurements, Recurring \| Foreign currency option contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign Currency Contracts, Asset	$ 391	$ 3,964