Stockholders' Equity - RSUs, PSUs and ESPP (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Stock-based compensation expense	$ 6,329,000	$ 1,467,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Award vesting percentage per year	25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance (in shares)	1,641,000
Granted (in shares)	1,072,000
Vested (in shares)	0
Cancelled/forfeited (in shares)	(11,000)
Ending balance (in shares)	2,702,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Beginning balance (in USD per share)	$ 20.07
Granted (in USD per share)	20.03
Forfeited (in USD per share)	20.04
Ending balance (in USD per share)	$ 20.04
Stock-based compensation expense	$ 4,100,000
Unrecognized stock-based compensation cost	$ 47,900,000
Weighted-average period of recognition	3 years 1 month 28 days
Performance-based Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage per year	25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Granted (in shares)	87,918
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Number of shares issued for each PSU (in shares)	1
Shares issuable pursuant to the ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period duration	6 months
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Stock-based compensation expense	$ 700,000	0
Maximum employee contribution as a percentage of salary	15.00%
Purchase price of common stock, percent	85.00%
Fair value of common stock	$ 6.02
Expected term (in years)	15 days
Risk-free interest rate	1.59%
Expected volatility	43.00%
Dividend yield	0.00%
Contributions withheld for taxes	$ 2,200,000	$ 0
Stock issued under ESPP (in shares)	0

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Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Deferral As A Percent Of Salary

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

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

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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 weighted average fair value at grant date for nonvested equity-based awards issued 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 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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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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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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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Price of a single share of a number of saleable stocks of a company.

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

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

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