Net Loss per Share - Calculation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net loss	$ (285,865)	$ (200,389)
Weighted average common shares used for basic and diluted net loss per share computation (in shares)	94,089	91,104
Net loss per common share:
Basic and Diluted (in usd per share)	$ (3.04)	$ (2.20)