Related Party Transactions (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Related Party Transaction [Line Items]
Cost of sales	$ 549,500,000	$ 999,500,000	$ 1,702,500,000	$ 3,663,000,000.0
Accounts payable to related party	900,000		900,000		$ 1,100,000
Cedar Cove Joint Venture
Related Party Transaction [Line Items]
Cost of sales	2,000,000.0	4,100,000	6,200,000	18,000,000.0
Accounts payable to related party	900,000		900,000		$ 1,100,000
GIP
Related Party Transaction [Line Items]
General and administrative expenses from transactions with related party	$ 200,000	$ 0	$ 200,000	$ 0