Noncontrolling Interests in Subsidiaries (Details) - USD ($) $ in Thousands	3 Months Ended		7 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Jul. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Noncontrolling Interests in Subsidiaries [Line Items]
Net Income	$ 3,189	$ 5,861		$ 12,533	$ 35,930
Net income attributable to noncontrolling interest	$ (1)	$ (544)		$ (8)	$ 7,239
SEA-Vista | Ocean Services
Noncontrolling Interests in Subsidiaries [Line Items]
Net Income			$ 14,800
Net income attributable to noncontrolling interest			$ 7,200