Incentive Compensation / 401(k) Retirement Plan - Summary of Changes in Non-Vested Restricted Shares (Details) - Restricted Stock	12 Months Ended
	Dec. 31, 2019 $ / shares shares
Number of Shares
Non-vested at beginning of period (in shares) | shares	7,060,334
Granted (in shares) | shares	103,000
Vested (in shares) | shares	(2,648,390)
Forfeited (in shares) | shares	(1,000,409)
Non-vested at end of period (in shares) | shares	3,514,535
Weighted Average Grant Date Fair Value per Share
Non-vested at beginning of period (in dollars per share) | $ / shares	$ 2.69
Granted (in dollars per share) | $ / shares	0.70
Vested (in dollars per share) | $ / shares	3.22
Forfeited (in dollars per share) | $ / shares	2.45
Non-vested at end of period (in dollars per share) | $ / shares	$ 2.30