Equity Method Investments - Schedule of Equity Investments in Affiliates (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2018
Schedule of Equity Method Investments [Line Items]
Investment Amount	$ 912,000,000	$ 926,000,000
Amberjack – Series A / Series B
Schedule of Equity Method Investments [Line Items]
Investment Amount	$ 418,000,000	$ 426,000,000.0
Amberjack - Series A
Schedule of Equity Method Investments [Line Items]
Ownership	75.00%	75.00%
Amberjack - Series B
Schedule of Equity Method Investments [Line Items]
Ownership	50.00%	50.00%
Mars
Schedule of Equity Method Investments [Line Items]
Ownership	71.50%	71.50%
Investment Amount	$ 160,000,000	$ 161,000,000
Bengal
Schedule of Equity Method Investments [Line Items]
Ownership	50.00%	50.00%
Investment Amount	$ 87,000,000	$ 88,000,000
Crestwood Permian Basin LLC (“Permian Basin”)
Schedule of Equity Method Investments [Line Items]
Ownership	50.00%	50.00%
Investment Amount	$ 90,000,000	$ 91,000,000
LOCAP
Schedule of Equity Method Investments [Line Items]
Ownership	41.48%	41.48%
Investment Amount	$ 9,000,000	$ 9,000,000
Explorer
Schedule of Equity Method Investments [Line Items]
Ownership	38.59%	38.59%
Investment Amount	$ 85,000,000	$ 88,000,000
Poseidon
Schedule of Equity Method Investments [Line Items]
Ownership	36.00%	36.00%
Investment Amount	$ 0	$ 0	$ 0
Colonial Pipeline Company (“Colonial”)
Schedule of Equity Method Investments [Line Items]
Ownership	16.125%	16.125%
Investment Amount	$ 30,000,000	$ 30,000,000
Proteus
Schedule of Equity Method Investments [Line Items]
Ownership	10.00%	10.00%
Investment Amount	$ 15,000,000	$ 15,000,000
Endymion
Schedule of Equity Method Investments [Line Items]
Ownership	10.00%	10.00%
Investment Amount	$ 18,000,000	$ 18,000,000