Revenue from Contracts with Customers (Contract with Customer, Asset and Liability) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Contract liability	$ 4,899	$ 7,061
Mid-Stream [Member]
Disaggregation of Revenue [Line Items]
Contract assets	7,976	12,921
Change in contract assets	(4,945)
Contract liability	4,899	7,061
Change in contract liabilities	(2,162)
Contract asset (liabilities), net	3,077	$ 5,860
Change in contract assets (liabilities)	$ (2,783)