Stock Plans and Stock-Based Compensation - Market-Based Restricted Stock Units - Additional Information (Details) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 7,785,000	$ 6,694,000
Dividend rate	0.00%
Unrecognized compensation expense	$ 16,500,000
Vesting of restricted stock units	0
Market-Based Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, number of stock unit grants in period	0
Share Based compensation threshold consecutive trading days	30 days
Stock-based compensation expense	$ 0	$ 3,700,000
Dividend rate	0.00%
Expected term (in years)	10 years
Unrecognized compensation expense	$ 0
Vesting of restricted stock units	657	222,624
Market-Based Restricted Stock Units \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, vesting stock price trigger	$ 35
Share-based compensation, share price on the date of issuance	$ 23.16
Risk-free interest rate	2.26%
Expected volatility	50.00%
Market-Based Restricted Stock Units \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, vesting stock price trigger	$ 55
Share-based compensation, share price on the date of issuance	$ 38.50
Risk-free interest rate	2.85%
Expected volatility	60.00%

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- Definition

Share based compensation vesting stock price trigger to achieve vesting of performance based restricted stock units.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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No definition available.

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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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