Income Taxes - Schedule of Effective Income Tax Rate Reconciliation for Continuing Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Statutory U.S. federal income tax rate	$ 12,737	$ 6,658	$ 2,978
State taxes, net of U.S. federal benefit	1,598	395	521
Foreign rate differential, including withholding taxes	(3,849)	(805)	(1,934)
Charges related to U.S. Government resolutions		2,050
Valuation allowances, net	3,548	6,149	10,952
Change in estimate on compensation expenses		(2,151)
Italian subsidiary intangible asset	(381)	(1,477)	(2,076)
Change of intention for foreign earnings	0	1,300
Domestic manufacturing deduction	(818)		(469)
Unrecognized tax benefits, net of settlements	6,002	3,049	406
Impact of the Tax Act	8,347
Other, net	1,916	359	471
Income tax expense	$ 29,100	$ 15,527	$ 10,849
Statutory U.S. federal income tax rate	35.00%	35.00%	35.00%
State taxes, net of U.S. federal benefit	4.40%	2.10%	6.10%
Foreign rate differential, including withholding taxes	(10.60%)	(4.20%)	(22.70%)
Charges related to U.S. Government resolutions		10.80%
Valuation allowances, net	9.70%	32.30%	128.70%
Change in estimate on compensation expenses		(11.30%)
Italian subsidiary intangible asset	(1.00%)	(7.80%)	(24.40%)
Change of intention for foreign earnings		6.80%
Domestic manufacturing deduction	(2.20%)		(5.50%)
Unrecognized tax benefits, net of settlements	16.50%	16.00%	4.80%
Impact of the Tax Act	22.90%
Other, net	5.30%	1.90%	5.50%
Income tax expense/effective rate	80.00%	81.60%	127.50%