Equity - Convertible Preferred Stock (Details) - USD ($) $ in Millions	Feb. 08, 2019	Feb. 08, 2019	Feb. 08, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Preferred stock, shares outstanding (in shares)				1,495,000
Preferred Stock
Class of Stock [Line Items]
Number of shares authorized (in shares)	10,000,000	10,000,000	10,000,000
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares outstanding (in shares)	1,495,000	1,495,000	1,495,000
Series B cumulative convertible perpetual preferred stock interest rate	6.875%		6.875%
Other long-term liabilities | Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock dividend payable	$ 14.6	$ 14.6	$ 14.6
Common Stock | Common Class A
Class of Stock [Line Items]
Number of shares authorized (in shares)	64,999,998	64,999,998	64,999,998
Class B Holder | Common Stock | Common Class B
Class of Stock [Line Items]
Shares issued (in shares)		1
Class C Holder | Common Stock | Common Class C
Class of Stock [Line Items]
Shares issued (in shares)		1
Cancellation And Discharge Of Old Notes | Former Holders Of Old Notes | Common Stock | Common Class A
Class of Stock [Line Items]
Shares issued (in shares)		8,900,000
Commitment To Backstop Exit Facility | Consenting Creditors | Common Stock | Common Class A
Class of Stock [Line Items]
Shares issued (in shares)		300,000
Weighted Average | 2019 Long Term Incentive Plan | Common Stock | Common Class A
Class of Stock [Line Items]
Number of shares authorized (in shares)	1,344,000	1,344,000	1,344,000