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Investments in Unconsolidated Affiliates (Details) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Jan. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2018 CNY (¥)	Nov. 30, 2017 USD ($)	Sep. 30, 2017	Apr. 30, 2014 USD ($)	Jan. 31, 2013 USD ($)
Investments in and Advances to Affiliates, Balance [Abstract]
Investments in unconsolidated affiliates		$ 32,469	$ 31,184	$ 32,469	$ 31,184
Foshan GWOYNG SMP Vehicle Climate Control & Cooling Products Co. Ltd. [Member]
Investments in and Advances to Affiliates, Balance [Abstract]
Investments in unconsolidated affiliates		$ 17,764	14,406	$ 17,764	14,406	$ 4,200	¥ 26,475,583			$ 14,000
Percentage of equity interest acquired		65.00%		65.00%		15.00%	15.00%			50.00%
Purchase price payment				$ 4,200
Purchases from equity method investment				14,900	15,100
Foshan FGD SMP Automotive Compressor Co. Ltd [Member]
Investments in and Advances to Affiliates, Balance [Abstract]
Investments in unconsolidated affiliates		$ 12,547	12,616	12,547	12,616			$ 12,500
Percentage of equity interest acquired								50.00%	50.00%
Purchase price payment	$ 5,700				6,800
Purchases from equity method investment				5,200
Orange Electronic Co., Ltd [Member]
Investments in and Advances to Affiliates, Balance [Abstract]
Investments in unconsolidated affiliates		$ 2,158	4,162	$ 2,158	4,162						$ 6,300
Percentage of equity interest acquired		19.40%		19.40%							25.00%
Purchases from equity method investment				$ 4,900	4,300
Impairment charge		$ 1,700	$ 1,800	$ 1,700	$ 1,800