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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Plans (Details) - shares	1 Months Ended	12 Months Ended
Stock-Based Compensation - Plans (Details) - shares	Dec. 31, 2016	Jan. 31, 2020	Feb. 01, 2018	Mar. 10, 2016
2008 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)				25,912,531
2008 Equity Incentive Plan \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period		10 years
Award vesting period		4 years
2016 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	10,000,000
Percentage of outstanding shares	4.00%
Number of shares authorized, annual increase			4,086,916
Number of shares available for futures issuance (in shares)		436,457