Long-term Incentive Compensation (Summary of Equity-Classified Restricted Stock Activity) (Details) - Restricted stock shares in Thousands	9 Months Ended
	Sep. 30, 2020 $ / shares shares
Number of Units
Beginning balance (in shares) | shares	1,480
Granted (in shares) | shares	570
Vested (in shares) | shares	(1,083)
Forfeited (in shares) | shares	(246)
Ending balance (in shares) | shares	721
Weighted Average Fair Value
Beginning balance (in dollars per share) | $ / shares	$ 7.00
Granted (in dollars per share) | $ / shares	2.88
Vested (in dollars per share) | $ / shares	5.30
Forfeited (in dollars per share) | $ / shares	7.71
Ending balance (in dollars per share) | $ / shares	$ 6.05