Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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- Definition

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+ References

No definition available.

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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Revenue - Contract Costs (Details) - USD ($) $ in Thousands	3 Months Ended
Revenue - Contract Costs (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Capitalized Contract Cost [Line Items]
Amortization of capitalized costs	$ 3,434	$ 3,986
Capitalized costs, net	8,339		$ 8,445
Tooling [Member]
Capitalized Contract Cost [Line Items]
Capitalized costs, net	6,058		6,155
Design Costs [Member]
Capitalized Contract Cost [Line Items]
Capitalized costs, net	2,281		2,285
Other Capitalized Contract Cost [Member]
Capitalized Contract Cost [Line Items]
Capitalized costs, net	$ 0		$ 5