Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Basic
Net Loss	$ (109,172)	$ (210,741)	$ (107,987)	$ (176,296)	$ (319,914)	$ (284,283)
Weighted average number of common shares (in shares)	346,875		345,941		346,778	345,946
Basic net loss per common share (USD per share)	$ (0.31)		$ (0.31)		$ (0.92)	$ (0.82)
Diluted
Net Loss	$ (109,172)	$ (210,741)	$ (107,987)	$ (176,296)	$ (319,914)	$ (284,283)
Weighted average number of common shares (in shares)	346,875		345,941		346,778	345,946
Dilutive stock options and non-participating RSUs (in shares)	0		0		0	0
Weighted average number of common and potential common shares (in shares)	346,875		345,941		346,778	345,946
Diluted net loss per common share (USD per share)	$ (0.31)		$ (0.31)		$ (0.92)	$ (0.82)