Cash repatriation of foreign earnings.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Date the credit facility terminates, in CCYY-MM-DD format.

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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Two Thousand Fifteen Credit Facility - Additional Information (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Total interest and commitments fees	$ 2,000,000	$ 4,000,000		$ 5,000,000	$ 10,000,000
2015 Credit Facility
Debt Instrument [Line Items]
Total interest and commitments fees				1,000,000	2,000,000
2015 Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Borrowing capacity under Credit Facility	1,200,000,000			$ 1,200,000,000
Interest rate description				Borrowings under the 2015 Credit Facility generally bear interest, at the Company’s option, at a rate per annum equal to either (i) the Eurocurrency Borrowing rate, or the adjusted LIBO rate for the interest period in effect for such borrowing; plus an applicable margin ranging from 1.25% to 2.00% (“Eurocurrency Spread”), based on the Company’s leverage ratio; or (ii) the Alternate Base Rate (“ABR”) Borrowing, which is the greatest of (a) the Prime Rate in effect on such day, (b) the New York Fed Bank Rate in effect on such day plus 1/2 of 1.00% per annum and (c) the Adjusted LIBO Rate (or LIBO rate multiplied by the Statutory Reserve Rate) for an interest period of one month plus 1.00%; in addition to an applicable margin ranging from 0.25% to 1.00% (“ABR Spread”), based on the Company’s leverage ratio. The Company may borrow from the 2015 Credit Facility in U.S. dollars, Euros and British pound sterling. In addition, our 2015 Credit Facility includes $15 million of borrowing capacity available for letters of credit and $40 million for Swing Line borrowings on same-day notice. As of September 30, 2019, we had issued $3 million of outstanding letters of credit under the 2015 Credit Facility. We are also required to pay a quarterly commitment fee, at an applicable rate ranging from 0.15% to 0.30%, on the daily unused portion of the revolving credit facility for each fiscal quarter and additional fees in connection with the issuance of letters of credit. As of September 30, 2019, our unused revolver capacity was subject to a commitment fee of 0.15%, given the Company’s leverage ratio
Credit facility, maturity date				May 12, 2022
Line Of Credit Facility Unused Capacity Commitment Fee Percentage				0.15%
Outstanding borrowings	0			$ 0		$ 0
Repayments of Debt					$ 230,000,000
Cash repatriation of foreign earnings			$ 325,000,000
2015 Credit Facility \| Revolving Credit Facility \| Adjusted London Interbank Offered Rate
Debt Instrument [Line Items]
Basis spread on variable rate				1.00%
2015 Credit Facility \| Revolving Credit Facility \| New York Fed Bank Rate
Debt Instrument [Line Items]
Basis spread on variable rate				0.50%
2015 Credit Facility \| Borrowings On Same Day Notice
Debt Instrument [Line Items]
Borrowing capacity under Credit Facility	40,000,000			$ 40,000,000
2015 Credit Facility \| Letter of Credit
Debt Instrument [Line Items]
Borrowing capacity under Credit Facility	15,000,000			15,000,000
Letters of credit outstanding amount	$ 3,000,000			$ 3,000,000
2015 Credit Facility \| Minimum \| Revolving Credit Facility
Debt Instrument [Line Items]
Line Of Credit Facility Unused Capacity Commitment Fee Percentage				0.15%
2015 Credit Facility \| Minimum \| Revolving Credit Facility \| Eurocurrency Spread
Debt Instrument [Line Items]
Basis spread on variable rate				1.25%
2015 Credit Facility \| Minimum \| Revolving Credit Facility \| Adjusted London Interbank Offered Rate
Debt Instrument [Line Items]
Basis spread on variable rate				0.25%
2015 Credit Facility \| Minimum \| Revolving Credit Facility \| ABR Spread
Debt Instrument [Line Items]
Basis spread on variable rate				0.25%
2015 Credit Facility \| Maximum \| Revolving Credit Facility
Debt Instrument [Line Items]
Line Of Credit Facility Unused Capacity Commitment Fee Percentage				0.30%
2015 Credit Facility \| Maximum \| Revolving Credit Facility \| Eurocurrency Spread
Debt Instrument [Line Items]
Basis spread on variable rate				2.00%
2015 Credit Facility \| Maximum \| Revolving Credit Facility \| Adjusted London Interbank Offered Rate
Debt Instrument [Line Items]
Basis spread on variable rate				1.00%
2015 Credit Facility \| Maximum \| Revolving Credit Facility \| ABR Spread
Debt Instrument [Line Items]
Basis spread on variable rate				1.00%