Net Income (Loss) Per Share (Computation of Basic Net Income (Loss) Per Share of Common Stock) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net Income (Loss) Per Share [Abstract]
Net income (loss)	$ (36,404)	$ (3,605)	$ (42,622)	$ (58,694)	$ (40,009)	$ (101,316)
Weighted average common shares outstanding	311,065,959		304,172,412		309,980,392	303,881,424
Minimum shares issuable under purchase contracts	12,994,501		16,465,704		13,328,888	16,465,704
Total weighted average shares outstanding	324,060,460		320,638,116		323,309,280	320,347,128
Basic and diluted net income (loss) per share	$ (0.11)		$ (0.13)		$ (0.12)	$ (0.32)