Incentive Based Compensation - Stock Options, Restricted Stock Awards and Restricted Stock Units (Details)	3 Months Ended
	Mar. 31, 2020 $ / shares shares
Number of Shares
Outstanding, beginning (in shares) | shares	5,659,731
Granted (in shares) | shares	1,132,808
Options Exercised (in shares) | shares	(52,333)
Canceled (in shares) | shares	(202,934)
Outstanding, ending (in shares) | shares	6,537,272
Weighted Average Exercise Price
Outstanding, beginning (in dollars per share) | $ / shares	$ 23.55
Granted (in dollars per share) | $ / shares	10.47
Options Exercised (in dollars per share) | $ / shares	7.22
Canceled (in dollars per share) | $ / shares	26.25
Outstanding, ending (in dollars per share) | $ / shares	21.33
Weighted Average Grant Date Fair Value
Weighted average grant date fair value (in dollars per share) | $ / shares	$ 3.82
Performance Unit Awards
Awards
Outstanding, ending (in shares) | shares	1,658,088
Restricted Stock Awards & Units
Awards
Outstanding, beginning (in shares) | shares	7,174,386
Granted (in shares) | shares	5,337,796
Stock Vested (in shares) | shares	(2,815,109)
Canceled (in shares) | shares	(200,750)
Outstanding, ending (in shares) | shares	9,496,323
Weighted Average Grant Date Fair Value
Outstanding, beginning (in dollars per share) | $ / shares	$ 15.88
Granted (in dollars per share) | $ / shares	8.55
Stock Vested (in dollars per share) | $ / shares	15.93
Canceled (in dollars per share) | $ / shares	14.71
Outstanding, ending (in dollars per share) | $ / shares	$ 11.77