Fair Value Measurements - Carrying Amounts and Fair Values (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current maturities of long-term debt	$ 0	$ (129,706)
Long-term debt	(833,879)	(621,849)
Carrying Amount \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	51,777	161,558
Restricted cash	23,525	6,688
Current maturities of long-term debt	0	(129,706)
Long-term debt	(833,879)	(621,849)
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)	(304)
Carrying Amount \| Fair Value, Measurements, Recurring \| Foreign currency option contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign Currency Contracts, Liability		(1,138)
Foreign Currency Contracts, Asset	3,964
Carrying Amount \| Fair Value, Measurements, Recurring \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps	(18,244)	(7,247)
Fair Value \| Level 1 \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	51,777	161,558
Restricted cash	23,525	6,688
Current maturities of long-term debt	0	0
Long-term debt	0	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, Asset	0	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 1 \| Fair Value, Measurements, Recurring \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps	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	0	(156,762)
Long-term debt	(830,203)	(628,476)
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)	(304)
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, Liability		(1,138)
Foreign Currency Contracts, Asset	3,964
Fair Value \| Level 2 \| Fair Value, Measurements, Recurring \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps	$ (18,244)	$ (7,247)

Fair value portion 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

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- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

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- Definition

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.

+ 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)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). 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 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

+ 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 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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