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Net Loss Per Share - Schedule of Share Totals with a Potentially Dilutive Impact (Details) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Apr. 14, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact (in shares)	9,889,785	9,053,129
Senior Notes Due 2025 \| Convertible Notes Payable
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Conversion price (in dollars per share)	$ 30.60		$ 30.60
Common stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact (in shares)	3,344,047	6,640,662
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact (in shares)	2,937,690	2,145,968
Performance-based restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact (in shares)	307,859	0
Shares related to convertible senior notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact (in shares)	2,768,114	0
Shares issuable as acquisition-related contingent consideration
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact (in shares)	344,436	0
Employee stock purchase plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact (in shares)	72,892	87,107
Restricted shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact (in shares)	114,747	179,392