Employee Stock Purchase Plan (ESPP), Weighted Average Purchase Price of Shares Purchased

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Common Warrants, Exercises in Period

+ References

No definition available.

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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

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of warrants or rights outstanding.

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- Definition

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

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

Amount of cash inflow from issuance of shares under share-based compensation arrangement, excluding stock option exercises.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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- Definition

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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- Definition

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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- 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

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Stockholders' Equity - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 52,030,000	$ 38,359,000	$ 41,785,000
Stock issued under ESPP (in shares)	253,301	377,530
Weighted average purchase price of shares purchased (in dollars per share)	$ 15.77	$ 7.88
Exercises in period, intrinsic value	$ 57,200,000	$ 16,800,000	600,000
Capitalized share-based compensation expense	$ 0	0	$ 0
Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards	3 years
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards	4 years
Performance-based restricted stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards	2 years
Performance-based restricted stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards	3 years
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from issuance of shares under ESPP	$ 4,000,000	$ 3,000,000
RSUs and PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average vesting period for recognition of compensation expense	1 year 4 months 13 days
Performance based restricted stock unit award granted to executive officers (in shares)	3,691,552
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)	$ 21.67
Awards forfeited	1,605,021
Unrecognized compensation costs related to restricted stock units	$ 67,400,000
2016 Performance Period \| Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance based restricted stock unit award granted to executive officers (in shares)	2,377,842
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)	$ 4.32
March 2018 PSU Grants [Member] \| Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards	3 years
Performance based restricted stock unit award granted to executive officers (in shares)	845,934
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)	$ 19.70
2017 Performance Period \| Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards	3 years
Performance based restricted stock unit award granted to executive officers (in shares)	1,822,284
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)	$ 8.91
2018 Performance Period \| Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards	3 years
Performance based restricted stock unit award granted to executive officers (in shares)	45,756
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)	$ 28.74
Share-based Compensation Award, Tranche Two \| 2016 Performance Period \| Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards	3 years
Common Stock Warrant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock warrants remaining	0
Weighted average exercise price (in dollars per share)	$ 12.00	$ 12.00
Common stock warrants exercised	100,000	100,000	0