Segment Information about Reported Product Revenues, Depreciation and Amortization and Operating Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Product revenues	$ 223,818	$ 206,012	$ 644,168	$ 606,132
Depreciation and amortization	7,800	8,634	23,123	24,565
Operating income (loss)	37,449	24,126	91,196	73,678
Operating Segments | Automotive Segments
Segment Reporting Information [Line Items]
Product revenues	202,734	197,480	603,131	589,426
Depreciation and amortization	6,956	6,974	20,157	20,374
Operating income (loss)	42,123	32,087	124,875	105,786
Operating Segments | Industrial Segments
Segment Reporting Information [Line Items]
Product revenues	21,084	8,532	41,037	16,706
Depreciation and amortization	450	879	1,343	1,650
Operating income (loss)	3,871	(716)	959	(5,317)
Reconciling Items
Segment Reporting Information [Line Items]
Depreciation and amortization	394	781	1,623	2,541
Operating income (loss)	$ (8,545)	$ (7,245)	$ (34,638)	$ (26,791)