Debt - Interest Rates (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
New Ultraco Debt Facility
Debt Instrument [Line Items]
Commitment fee percentage	40.00%	40.00%	40.00%	40.00%
Norwegian Bond Debt Facility
Debt Instrument [Line Items]
Interest rate		8.25%		8.25%
Norwegian Bond Debt Facility | Senior Subordinated Notes
Debt Instrument [Line Items]
Interest rate	8.25%		8.25%
Super Senior Facility
Debt Instrument [Line Items]
Commitment fee percentage	40.00%	40.00%	40.00%	40.00%
Super Senior Facility | Senior Subordinated Notes
Debt Instrument [Line Items]
Interest rate	2.58%	3.96%	2.58%	5.21%
Holdco Revolving Facility
Debt Instrument [Line Items]
Commitment fee percentage	40.00%		40.00%
Minimum | Convertible Bond Debt
Debt Instrument [Line Items]
Interest rate	5.00%	500.00%		500.00%
Minimum | New Ultraco Debt Facility
Debt Instrument [Line Items]
Interest rate	2.60%	2.73%	2.60%	2.73%
Minimum | Super Senior Facility | Senior Subordinated Notes
Debt Instrument [Line Items]
Interest rate	2.24%	2.40%	2.24%	2.90%
Minimum | Holdco Revolving Facility | Senior Subordinated Notes
Debt Instrument [Line Items]
Interest rate	2.60%		2.60%
Weighted Average | Convertible Bond Debt
Debt Instrument [Line Items]
Interest rate	10.14%	10.14%	10.14%	10.14%
Weighted Average | New Ultraco Debt Facility
Debt Instrument [Line Items]
Interest rate		3.90%		4.63%
Weighted Average | New Ultraco Debt Facility | Senior Subordinated Notes
Debt Instrument [Line Items]
Interest rate	3.25%		3.23%
Weighted Average | Norwegian Bond Debt Facility
Debt Instrument [Line Items]
Interest rate		8.94%		9.04%
Weighted Average | Norwegian Bond Debt Facility | Senior Subordinated Notes
Debt Instrument [Line Items]
Interest rate	9.13%		9.00%
Weighted Average | Holdco Revolving Facility | Senior Subordinated Notes
Debt Instrument [Line Items]
Interest rate	5.05%		5.05%
Maximum | New Ultraco Debt Facility
Debt Instrument [Line Items]
Interest rate	2.72%	4.27%	2.72%	4.68%