Convertible Senior Notes - Capped Call and Common Stock Forward (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended			3 Months Ended			6 Months Ended
	May 18, 2020	Nov. 30, 2020	Aug. 31, 2020	May 31, 2020	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2021	Jan. 31, 2021	Jan. 07, 2021	Jan. 01, 2021	Jun. 30, 2020	May 29, 2020	Sep. 30, 2019	Mar. 31, 2018
Capped Call and Common Stock Forward
Interest rate (as a percent)											3.75%
Share Price		$ 22.25	$ 10.25
Common stock shares issued		43,700,000	35,276,250
Common Stock Forward
Capped Call and Common Stock Forward
Common stock shares issued					2,200,000	5,900,000	4,400,000
Net cost incurred								$ 27,500
3.75% Convertible Senior Notes
Capped Call and Common Stock Forward
Interest rate (as a percent)	3.75%			3.75%	3.75%	3.75%		3.75%					3.75%
Principal amount	$ 200,000			$ 212,463	$ 197,278			$ 197,278					$ 12,500
Share Price					$ 34.19			$ 34.19
Percentage of principal amount to be redeemed	100.00%
3.75% Convertible Senior Notes | Capped Call
Capped Call and Common Stock Forward
Capped call options amount	$ 16,200
Cap price	$ 6.7560
Premium (as a percent)	60.00%
Share Price	$ 4.11
5.5% Convertible Senior Notes
Capped Call and Common Stock Forward
Interest rate (as a percent)	5.50%			5.50%	5.50%		5.50%	5.50%	5.50%	5.50%		5.50%			5.50%
Principal amount	$ 100,000						$ 33,500			$ 160					$ 100,000
5.5% Convertible Senior Notes | Capped Call
Capped Call and Common Stock Forward
Capped call options amount				$ 16,000
Recorded in additional paid-in capital				$ 24,200
Percentage of principal amount to be redeemed				100.00%
5.5% Convertible Senior Notes | Common Stock Forward
Capped Call and Common Stock Forward
Common stock shares issued								14,397,906
7.5% Convertible Senior Note
Capped Call and Common Stock Forward
Interest rate (as a percent)														7.50%