Revenue Recognition - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Deferred Revenue Arrangement [Line Items]
Aggregate amount of transaction price allocated to material rights that remain unsatisfied	$ 747
Revenue expected to be recognized in next 3 months	42.00%
Revenue expected to be recognized in 2020	33.00%
Revenue expected to be recognized in 2021	9.00%
Revenue expected to be recognized in 2022	9.00%
Revenue expected to be recognized in 2023	7.00%
Unearned revenue	$ 747	$ 1,597
Automotive Segments
Deferred Revenue Arrangement [Line Items]
Unearned revenue	$ 747	$ 1,597

Deferred revenue expected to be recognized in remainder of fiscal year.

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- Definition

Deferred revenue expected to be recognized in year five.

+ References

No definition available.

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- Definition

Deferred revenue expected to be recognized in year four.

+ References

No definition available.

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- Definition

Deferred revenue expected to be recognized in year three.

+ References

No definition available.

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- Definition

Deferred revenue expected to be recognized in year two.

+ References

No definition available.

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- Definition

Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(5))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130556-203045

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