Commitments and Contingencies - Schedule of Changes in Warranty Reserves (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commitments And Contingencies [Abstract]
Balance, beginning of the period	$ 2,427	$ 1,788	$ 1,894
Accruals	3,486	3,464	2,405
Usage	(3,472)	(2,825)	(2,511)
Balance, end of the period	$ 2,441	$ 2,427	$ 1,788

Commitments and Contingencies [Abstract]

No definition available.

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- Definition

Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(2))
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

+ Details

Name:	us-gaap_ProductWarrantyAccrualPayments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of increase in the standard and extended product warranty accrual from warranties issued.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(3))
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1),(c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

+ Details

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Balance Type:	credit
Period Type:	instant