Segment Information about Reported Product Revenues, Depreciation and Amortization and Operating Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Product revenues	$ 243,326	$ 266,400	$ 501,247	$ 530,986
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Depreciation and amortization	$ 11,165	$ 12,931	$ 22,217	$ 25,823
Operating income (loss)	20,057	15,593	41,902	36,242
Automotive Segments
Segment Reporting Information [Line Items]
Product revenues	229,700	243,150	472,057	485,571
Industrial Segments
Segment Reporting Information [Line Items]
Product revenues	13,626	23,250	29,190	45,415
Operating Segments \| Automotive Segments
Segment Reporting Information [Line Items]
Product revenues	$ 229,700	$ 243,150	$ 472,057	$ 485,571
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Depreciation and amortization	$ 10,327	$ 11,263	$ 20,490	$ 22,368
Operating income (loss)	37,931	37,240	77,827	78,404
Operating Segments \| Industrial Segments
Segment Reporting Information [Line Items]
Product revenues	$ 13,626	$ 23,250	$ 29,190	$ 45,415
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Depreciation and amortization	$ 416	$ 1,008	$ 839	$ 2,063
Operating income (loss)	$ (4,121)	$ (7,881)	$ (8,635)	$ (14,561)
Reconciling Items
Segment Reporting Information [Line Items]
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Depreciation and amortization	$ 422	$ 660	$ 888	$ 1,392
Operating income (loss)	$ (13,753)	$ (13,766)	$ (27,290)	$ (27,601)

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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