v3.20.2

Stockholders' Equity - Restricted and Performance Restricted Stock Units (Details)	9 Months Ended
	Sep. 30, 2020 $ / shares shares
Restricted stock units
Restricted Stock Units [Roll Forward]
Outstanding balance at the beginning of the period (in shares) | shares	2,281,142
Granted (in shares) | shares	1,911,308
Vested (in shares) | shares	(550,624)
Forfeited (in shares) | shares	(209,997)
Outstanding balance at the end of the period (in shares) | shares	3,431,829
Grant Date Fair Value [Roll Forward]
Outstanding at the beginning of the period (in dollars per share) | $ / shares	$ 40.49
Granted (in dollars per share) | $ / shares	20.66
Vested (in dollars per share) | $ / shares	51.84
Forfeited (in dollars per share) | $ / shares	30.17
Outstanding at the end of the period (in dollars per share) | $ / shares	$ 28.25
Restricted stock units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted stock units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Performance restricted stock units
Restricted Stock Units [Roll Forward]
Outstanding balance at the beginning of the period (in shares) | shares	1,413,773
Granted (in shares) | shares	657,723
Vested (in shares) | shares	(38,748)
Forfeited (in shares) | shares	(272,584)
Outstanding balance at the end of the period (in shares) | shares	1,760,164
Grant Date Fair Value [Roll Forward]
Outstanding at the beginning of the period (in dollars per share) | $ / shares	$ 28.12
Granted (in dollars per share) | $ / shares	22.45
Vested (in dollars per share) | $ / shares	22.38
Forfeited (in dollars per share) | $ / shares	48.87
Outstanding at the end of the period (in dollars per share) | $ / shares	$ 22.91

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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 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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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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Net number of non-option equity instruments granted to participants.

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