Segment Reporting - Segment Information About Reported Segment Product Revenues by Product Category (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Product revenues	$ 136,061	$ 243,326	$ 364,674	$ 501,247
Automotive Segments
Segment Reporting Information [Line Items]
Product revenues	124,386	229,700	340,858	472,057
Automotive Segments | Climate Control Seats (CCS)
Segment Reporting Information [Line Items]
Product revenues	49,879	88,437	132,407	182,791
Automotive Segments | Seat Heaters
Segment Reporting Information [Line Items]
Product revenues	33,342	73,628	97,874	147,548
Automotive Segments | Automotive Cables
Segment Reporting Information [Line Items]
Product revenues	9,833	22,206	31,973	45,955
Automotive Segments | Steering Wheel Heaters
Segment Reporting Information [Line Items]
Product revenues	7,980	16,029	27,215	32,999
Automotive Segments | Battery Thermal Management (BTM)
Segment Reporting Information [Line Items]
Product revenues	6,653	8,896	17,862	19,641
Automotive Segments | Electronics
Segment Reporting Information [Line Items]
Product revenues	13,488	11,454	23,864	24,306
Automotive Segments | Other Automotive
Segment Reporting Information [Line Items]
Product revenues	3,211	9,050	9,663	18,817
Industrial Segments
Segment Reporting Information [Line Items]
Product revenues	11,675	13,626	23,816	29,190
Industrial Segments | Medical
Segment Reporting Information [Line Items]
Product revenues	$ 11,675	9,881	$ 23,816	18,068
Industrial Segments | GPT
Segment Reporting Information [Line Items]
Product revenues		$ 3,745		7,704
Industrial Segments | CSZ-IC
Segment Reporting Information [Line Items]
Product revenues				$ 3,418