Income Taxes - Additional Information (Detail) € in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017 USD ($)	Jan. 01, 2018 USD ($)	Dec. 31, 2017 EUR (€)
Income Taxes [Line Items]
Effective tax rate	24.70%	24.60%
U.S. statutory tax rate	21.00%	34.00%	35.00%
Net operating loss carry forwards, expiration description			Expire at various dates through December 2037.
Business tax credits carry forwards, expiration description			Expire at various dates through December 2037.
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			$ 12,812
Tax cuts and jobs Act, increased tax provision on undistributed and previously untaxed post-1986 earnings and profits of the specified foreign corporation			3,266
Accounting Standards Update 2016-06 | Other Assets
Income Taxes [Line Items]
Impact on assets and liabilities due to change in accounting principle				$ 5,609
Accounting Standards Update 2016-06 | Deferred Tax Liabilities
Income Taxes [Line Items]
Impact on assets and liabilities due to change in accounting principle				4,932
Accounting Standards Update 2016-06 | Accumulated Deficit
Income Taxes [Line Items]
Impact on assets and liabilities due to change in accounting principle				$ 677
Domestic Tax Authority
Income Taxes [Line Items]
Business tax credits carry forwards			297
State
Income Taxes [Line Items]
Business tax credits carry forwards			99
United States
Income Taxes [Line Items]
Net operating loss carry forwards			19,652
Germany
Income Taxes [Line Items]
Net operating loss carry forwards			$ 743		€ 603