Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 25
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=51819886&loc=SL6014347-161799

Convertible Senior Notes - Narrative (Details)		1 Months Ended	12 Months Ended
Convertible Senior Notes - Narrative (Details)	Dec. 31, 2020 USD ($)	Oct. 05, 2020 USD ($) day $ / shares	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Net equity component of debt issuance costs			$ 75,333,000
Borrowing rate \| Discounted Cash Flow
Debt Instrument [Line Items]
Debt borrowing rate (percent)	9.70%		9.70%
Convertible notes \| Convertible Senior Notes Due 2027
Debt Instrument [Line Items]
Debt principal issued	$ 230,000,000.0		$ 230,000,000.0
Interest rate (percent)	2.75%		2.75%
Debt issuance costs		$ 7,500,000
Net proceeds from issuance of Convertible Senior Notes			$ 222,500,000
Conversion ratio		0.0411794
Initial conversion price (in usd per share) \| $ / shares		$ 24.28
Multiples of principal amounts required upon conversion		$ 1,000
Fair value of convertible debt		152,100,000
Equity component - net carrying value		77,900,000
Debt component of debt issuance costs		4,900,000
Equity component of debt issuance costs		2,500,000
Net equity component of debt issuance costs		75,300,000
Debt discount and issuance costs	$ 80,647,000	$ 82,800,000	$ 80,647,000
Effective interest rate (percent)		9.90%
Remaining term	6 years 8 months 12 days	7 years
Convertible notes \| Convertible Senior Notes Due 2027 \| Debt conversion, scenario one
Debt Instrument [Line Items]
Closing stock price threshold as percentage of conversion price (percent)		130.00%
Number of trading days \| day		20
Consecutive trading days \| day		30
Convertible notes \| Convertible Senior Notes Due 2027 \| Debt conversion, scenario two
Debt Instrument [Line Items]
Closing stock price threshold as percentage of conversion price (percent)		98.00%
Number of trading days \| day		5
Consecutive trading days \| day		10
Convertible notes \| Convertible Senior Notes Due 2027 \| Debt conversion, scenario three
Debt Instrument [Line Items]
Closing stock price threshold as percentage of conversion price (percent)		130.00%
Number of trading days \| day		20
Consecutive trading days \| day		30
Debt conversion, percentage of principal (percent)		100.00%