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The estimated tax amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Percentage of reduction in interest rate on senior notes.

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

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Average fixed interest rate related to the group of interest rate derivatives.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fixed interest rate related to the interest rate derivative.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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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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Date the derivative contract matures, in CCYY-MM-DD format.

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The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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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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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Derivative Financial Instruments - Additional Information (Details) € in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) item	Jun. 30, 2018 USD ($)	Jun. 30, 2019 EUR (€)	Dec. 31, 2018 USD ($)	Dec. 31, 2017
Derivative [Line Items]
Foreign currency unrealized losses expected to be reclassified into earnings over next twelve months	$ (8,700,000)		$ (8,700,000)
Foreign currency unrealized gains expected to be reclassified into earnings over next twelve months, tax	$ 3,000,000.0		$ 3,000,000.0
3.95% senior unsecured notes due 2027
Derivative [Line Items]
Debt instrument, interest rate	3.95%		3.95%		3.95%		3.95%
Interest Rate Swap Agreements
Derivative [Line Items]
Derivative fixed interest rate (as a percent)	0.52%		0.52%		0.52%
Carrying value / fair value of derivative liabilities included in other liabilities	$ 800,000		$ 800,000			$ 500,000
Interest Rate Swap Agreements \| U.S. dollars
Derivative [Line Items]
Variable Rate Basis			LIBOR
Interest Rate Swap Agreements \| EUR
Derivative [Line Items]
Variable Rate Basis			Euribor
Swaps maturing September 2019
Derivative [Line Items]
Average fixed interest rate (as a percent)	1.09%		1.09%		1.09%
Interest Rate Swap Final Maturity Period One
Derivative [Line Items]
Final maturity date of swap amortization			Jun. 30, 2023
Interest Rate Swap Final Maturity Period Two
Derivative [Line Items]
Final maturity date of swap amortization			Jun. 30, 2024
Treasury Lock \| Interest Lock Agreement \| 3.95% senior unsecured notes due 2027
Derivative [Line Items]
Percentage of reduction in effective interest rate on senior notes			0.25%
Foreign Currency Forward Exchange Contracts
Derivative [Line Items]
Number of credit contingency features \| item			0
Foreign Currency Forward Exchange Contracts \| Cash Flow Hedging
Derivative [Line Items]
Gains (losses) in other comprehensive income, effective portion	$ 5,200,000	$ 20,900,000	$ 8,800,000	$ 12,500,000
Commodity Swap Agreements
Derivative [Line Items]
Carrying value / fair value of derivative liabilities included in other liabilities	4,700,000		4,700,000
Notional amount	20,600,000		20,600,000
Designated as Hedging Instrument \| Interest Rate Swap Agreements
Derivative [Line Items]
Floating rate obligation	50,000,000.0		50,000,000.0		€ 44.9
Carrying value / fair value of derivative assets included in other assets	100,000		100,000			600,000
Designated as Hedging Instrument \| Foreign Currency Forward Exchange Contracts
Derivative [Line Items]
Carrying value / fair value of derivative assets included in other assets	400,000		400,000			1,300,000
Carrying value / fair value of derivative liabilities included in other liabilities	18,700,000		18,700,000			15,300,000
Notional amount	412,100,000		412,100,000			416,500,000
Designated as Hedging Instrument \| Foreign Currency Forward Exchange Contracts \| Other Noncurrent Liabilities
Derivative [Line Items]
Carrying value / fair value of derivative liabilities included in other liabilities	6,700,000		6,700,000
Designated as Hedging Instrument \| Foreign Currency Forward Exchange Contracts \| Cash Flow Hedging
Derivative [Line Items]
Net gain (loss) recognized in gross margin	(2,800,000)	1,100,000	(4,600,000)	3,400,000
Not Designated as Hedging Instrument \| Foreign Currency Forward Exchange Contracts
Derivative [Line Items]
Carrying value / fair value of derivative assets included in other assets	100,000		100,000			$ 300,000
Carrying value / fair value of derivative liabilities included in other liabilities	100,000		100,000
Foreign exchange net gains (losses) on derivative contracts not designated as hedges	$ 900,000	$ 6,000,000.0	$ 600,000	$ 4,000,000.0