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Tax Cuts and Jobs Act of 2017, incomplete accounting, change in tax rate, deferred tax liability, provisional income tax benefit.

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Tax Cuts and Jobs Act of 2017, incomplete accounting, transition tax for accumulated foreign earnings, provisional income tax expense.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to disposition of asset. Includes, but is not limited to, intra-entity transfer of asset other than inventory.

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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A description of the limitations on the use of all operating loss carryforwards available to reduce future taxable income.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Description of the limitation related to use of the tax credit carryforward.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes - Additional Information (Detail) € in Thousands, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017 USD ($)	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017 USD ($)	Jan. 01, 2018 USD ($)	Dec. 31, 2017 EUR (€)
Income Taxes [Line Items]
Effective tax rate	18.70%	(130.90%)	22.10%	(49.00%)
U.S. statutory tax rate	21.00%	34.00%	21.00%	34.00%	35.00%
Income tax benefit from sale of intellectual property		$ (5,625)
Valuation allowance increase (decrease)		$ (9,200)
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