Commitments and Contingencies - Schedule of Changes in Aggregate Product Warranty Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Commitments And Contingencies Disclosure [Abstract]
Product warranty liability at beginning of period	$ 6,171	$ 3,480
Accruals for warranties issued	1,841	5,275
Adjustments related to preexisting warranties (including changes in estimates)	200	200
Settlements made (in cash or in kind)	(967)	(2,784)
Product warranty liability at end of period	$ 7,245	$ 6,171

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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.

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Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

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

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