Common Stock, Capital Shares Reserved for Future Issuance, Annual Increase, Percentage of Outstanding Common Stock

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period, Achievement Percentage

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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- Definition

Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Amount of cost capitalized for award under share-based payment arrangement.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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.

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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Percentage of vesting of award under share-based payment arrangement.

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- Definition

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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Purchase price of common stock expressed as a percentage of its fair value.

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- Definition

Per share amount of par value or stated value of stock classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable.

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The maximum number of securities classified as temporary equity that are permitted to be issued by an entity's charter and bylaws. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Equity and Equity Compensation Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jun. 01, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jul. 27, 2017	Jul. 26, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, authorized (in shares)		500,000,000	500,000,000
Common stock, par value (in dollars per share)		$ 0.001	$ 0.001
Preferred stock, outstanding (in shares)			0
Stock-based compensation expense		$ 36,973	$ 27,814	$ 20,438
Stock-based compensation capitalized		$ (2,348)	$ (1,280)	(522)
Redeemable convertible preferred stock, authorized (in shares)		10,000,000	10,000,000
Temporary Equity, Par or Stated Value Per Share		$ 0.001	$ 0.001
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 816
2004 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life		10 years
Award vesting period		4 years
2017 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)		3,009,662	2,400,256
2017 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)		21,502,858	19,916,092			7,898,159
Percentage of common stock, outstanding		5.00%
Expected life		10 years
Award vesting period		4 years
Restricted stock units outstanding (in shares)		4,459,743	5,023,412
Employee Stock \| 2004 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)		0
Employee Stock \| 2017 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)					1,600,000
Percentage of common stock, outstanding		1.00%
Purchase price of common stock, percentage of market price of common stock		85.00%
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, period for recognition		9 months 18 days
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, period for recognition		2 years 6 months 18 days
Restricted stock units outstanding (in shares)		4,459,743	5,023,412
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 113,101
Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding (in shares)		400,873
Award requisite service period, achievement percentage		100.00%
Stock-based compensation expense		$ 2,854	$ 284	$ 610
Minimum \| 2017 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		2 years
Minimum \| Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage		0.00%
Maximum \| 2017 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		4 years
Maximum \| Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage		200.00%
Chief Executive Officer \| Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	150,000
Options granted (in dollars per share)	$ 27.50
Chief Executive Officer \| Maximum \| Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	300,000