Consolidated Balance Sheet Components - Schedule of Allowance for Sales Incentives (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ (16,213)
Ending balance	(15,219)	$ (16,213)
Allowance for Sales Incentives
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning balance	(8,503)	(7,642)
Charged to revenue	(28,048)	(36,626)
Utilization of sales return/incentive reserve	26,052	35,765
Ending balance	$ (10,499)	$ (8,503)

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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