Fair Value of Financial Instruments - Capped Calls (Details) - Capped Calls with Respect to 2024 Convertible Notes and 2026 Convertible Notes	1 Months Ended
Aug. 31, 2019 $ / shares $ / item
Capped Calls
Strike price (in dollars per share) \| $ / shares	$ 13.39
Cap price \| $ / item	17.05

Exercise or strike price stated in the contract for options indexed to the issuer's equity shares.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(1)
-SubTopic 10
-Topic 480
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481648/480-10-50-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)(2)
-SubTopic 40
-Topic 815
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

Name:	us-gaap_OptionIndexedToIssuersEquityStrikePrice1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration