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Derivative Contracts - Narrative (Details) - USD ($) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016 | Dec. 31, 2016 | May 09, 2016
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Cash collateral provided | $ 0 |  | $ 0 |  | $ 0 |
Goldman Sachs International |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative notional amount |  |  |  |  |  | $ 256,300,000
Foreign Exchange Contracts | Not Designated as Hedging Instruments |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative notional amount | 814,600,000 |  | 814,600,000 |  | 665,600,000 |
Foreign Exchange Contracts | Not Designated as Hedging Instruments | Change in Fair Value of Derivatives |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative instruments not designated as hedging instruments, gain (loss), net | 17,600,000 | $ 200,000 | 20,700,000 | $ (4,200,000) |  |
Foreign Exchange Contracts | Designated as Hedging Instrument |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Cash collateral provided | 0 |  | 0 |  | 2,200,000 |
Foreign Exchange Contracts | Designated as Hedging Instrument | General and Administrative Expense |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Foreign exchange contract settlement | 900,000 | (1,400,000) | 1,200,000 | (2,500,000) |  |
Foreign Exchange Contracts | Designated as Hedging Instrument | Net change from current period hedged transactions |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Net unrealized gain (loss) | 2,400,000 | (2,900,000) | 3,700,000 | (5,000,000) |  |
Foreign Exchange Contracts | Derivatives at Fair Value | Not Designated as Hedging Instruments |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative notional amount | 547,300,000 |  | 547,300,000 |  | 240,200,000 |
Foreign Exchange Contracts | Derivatives at Fair Value | Designated as Hedging Instrument |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative notional amount | 54,600,000 |  | 54,600,000 |  | 0 |
Foreign Exchange Contracts | Liabilities under Derivative Contracts | Designated as Hedging Instrument |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative notional amount | 0 |  | 0 |  | $ 108,600,000 |
Interest Rate Swaps | Not Designated as Hedging Instruments | Change in Fair Value of Derivatives |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative instruments not designated as hedging instruments, gain (loss), net | $ 0 | $ (600,000) | $ 0 | $ (3,400,000) |  |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624258-113959 + Details
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- Definition 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. + Details
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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959 + Details
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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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- Definition Amount of gain (loss) from the increase (decrease) in fair value of foreign currency derivatives and nonderivative instruments designated as fair value hedging instruments which were recognized in earnings, net of offsets by the gain (loss) on the hedged item to the extent that the fair value hedge was determined to be effective. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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