Employee service share based compensation nonvested awards compensation cost not yet recognized date for recognition.

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- Definition

Employee stock purchase plan maximum offering period.

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Number of common stock voting rights.

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

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

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

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Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

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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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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

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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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Number of additional shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of options outstanding, including both vested and non-vested options.

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Stockholders' Equity and Stock-Based Compensation - Additional Information (Details)	1 Months Ended	3 Months Ended		9 Months Ended
	Jan. 31, 2019 shares	Sep. 30, 2019 USD ($) VotingRight shares	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) VotingRight shares	Sep. 30, 2018 USD ($)	Dec. 31, 2018 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, authorized		200,000,000		200,000,000		200,000,000
Common stock, Issued		37,558,984		37,558,984		35,385,810
Common stock, outstanding		37,558,984		37,558,984		35,385,810
Dividends paid or declared \| $				$ 0
Common stock voting rights				Each share of common stock has the right to one vote on all matters submitted to a vote of stockholders.
Number of common stock voting rights \| VotingRight		1		1
Options outstanding		866,000		866,000		1,303,000
Stock-based compensation expense \| $		$ 14,094,000	$ 5,683,000	$ 43,398,000	$ 16,102,000
Unrecognized stock-based compensation costs related to non-vested awards \| $		3,090,000		$ 3,090,000
Weighted-average period for unrecognized compensation cost expected to be recognized				2 years 3 months 18 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation costs \| $		$ 98,961,000		$ 98,961,000
Weighted-average period for unrecognized compensation cost expected to be recognized				3 years
2010 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grants		0		0
Options outstanding		526,683		526,683
2015 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grants		2,042,597		2,042,597
Increase in share reserve under the plan	1,592,361
2014 Equity Incentive Plan \| Practice XYZ, Inc.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grants		0		0
Options outstanding		503		503
2014 Equity Incentive Plan \| Portfolium ,Inc
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grants		0		0
Options outstanding		33,002		33,002
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grants		696,557		696,557
Increase in share reserve under the plan	333,333
Initial offering expiration period				27 months
Percentage of discount through payroll deductions to eligible employees to purchase common stock				15.00%
Unrecognized stock-based compensation costs \| $		$ 351,000		$ 351,000
Weighted average date for unrecognized compensation cost to expected to be recognized				Nov. 30, 2019
2019 Bonus Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense \| $				$ 0
Unrecognized stock-based compensation costs \| $		$ 0		$ 0