Debt - Additional Information (Detail) € in Millions					1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 22, 2016 EUR (€) Installment	May 27, 2015 EUR (€)	May 11, 2015 USD ($)	Mar. 26, 2015 USD ($)	Jul. 31, 2016 EUR (€)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jun. 30, 2016 USD ($)
Debt Instrument [Line Items]
Short-term borrowings outstanding						$ 2,832,000		$ 2,832,000		$ 0
Lines of credit						47,500,000		47,500,000		53,400,000
Proceeds from the issuance of debt								80,000,000
Increase in line of credit facility				$ 500,000,000
Borrowings under the Term Facility						55,543,000		55,543,000		$ 86,641,000
Interest expense, net						9,214,000	$ 7,666,000	18,538,000	$ 15,925,000
Interest expense, gross						10,100,000	8,600,000	20,300,000	17,400,000
Non-cash portion of interest expense						900,000	700,000	1,900,000	1,400,000
Cash portion of gross interest expense						9,200,000	7,900,000	18,400,000	16,000,000
Interest income						900,000	$ 900,000	$ 1,800,000	$ 1,500,000
Innovative Systems GmbH [Member]
Debt Instrument [Line Items]
Loss contingency settlement agreement date								Jun. 22, 2016
Percentage of shareholders involved in contingent purchase Price	80.05%
Contingent purchase price settlement agreement terms								Under the terms of the agreement, we will pay the IS Obligation in accordance with the following schedule: an initial payment of €24.8 million which was paid in July 2016 and four installment payments of €13 million due every July 1st from 2017 through 2020
Remaining disputed amount, each installment payable | €	€ 13.0
Remaining disputed amount, initial payment paid | €					€ 24.8
Number of installments after initial payment | Installment	4
First installment due date								Jul. 01, 2017
Final installment due date								Jul. 01, 2020
Discount percentage on early installments	8.00%									8.00%
Multi-Currency Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Unsecured revolving credit facility, period of agreement, in years				5 years
Aggregate commitment				$ 1,200,000,000
Current borrowing capacity				750,000,000
Borrowings under the Term Facility						4,100,000		$ 4,100,000		$ 4,100,000
Unused available credit						682,900,000		682,900,000		672,900,000
Fees and other expenses						3,000,000		3,000,000
Letters of Credit [Member]
Debt Instrument [Line Items]
Aggregate commitment				$ 50,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Lines of credit						$ 513,000,000		$ 513,000,000		523,000,000
2.000 Percent Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate						2.00%		2.00%
4.150 Percent Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate						4.15%		4.15%
Senior Notes [Member]
Debt Instrument [Line Items]
Debt issuance cost to be amortized						$ 5,754,000		$ 5,754,000		6,173,000
Senior Notes [Member] | 2.000 Percent Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, aggregate principal amount | €		€ 350.0
Debt instrument, interest rate		2.00%
Debt instrument, maturity date								May 27, 2022
Debt instrument, par value percentage		99.613%
Debt discount to be amortized		€ 1.4				1,117,000		$ 1,117,000		1,283,000
Debt issuance cost to be amortized | €		€ 2.6
Effective interest rate		2.06%
Proceeds from the issuance of debt | €		€ 346.0
Senior Notes [Member] | 4.150 Percent Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, aggregate principal amount			$ 400,000,000
Debt instrument, interest rate			4.15%
Debt instrument, maturity date								May 15, 2025
Debt instrument, par value percentage			99.336%
Debt discount to be amortized			$ 2,700,000			$ 2,293,000		$ 2,293,000		$ 2,407,000
Debt issuance cost to be amortized			$ 3,800,000
Effective interest rate			4.232%
Proceeds from the issuance of debt			$ 393,500,000