Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Line Items]
Provisional estimate recorded related to re-measurement of deferred tax balance	$ 34,600
Provisional amount recorded in connection with the transition tax offset by foreign tax credits	7,700
Amount expected to be utilized of tax credit carry forwards expiring in the and beyond the stated year	2,000
Valuation allowance	20,178	$ 18,907
Unrecognized tax benefits, impact on effective tax rate	2,800	500	$ 500
Accrued interest and penalties	100	100	200
Increase (decrease) in income tax expense		$ (100)	$ (2,300)
Unrecognized tax benefits, gross	100
Foreign Countries
Income Taxes [Line Items]
Valuation allowance	18,700
Foreign Countries
Income Taxes [Line Items]
Net operating loss carryforwards, foreign	26,400
California enterprise zone
Income Taxes [Line Items]
California enterprise zone tax credits	3,500
California enterprise zone | California Enterprise Zone
Income Taxes [Line Items]
Valuation allowance	$ 1,500