Acquisitions and Other Transactions - April 2020 Transaction (Details)		3 Months Ended													12 Months Ended
	Apr. 01, 2020 USD ($) numberOfQuarters $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Sep. 30, 2020 $ / shares	Jun. 30, 2020 $ / shares	Mar. 31, 2020 $ / shares	Dec. 31, 2019 USD ($) $ / shares shares	Sep. 30, 2019 $ / shares	Jun. 30, 2019 $ / shares	Mar. 31, 2019 $ / shares	Dec. 31, 2018 $ / shares shares	Sep. 30, 2018 $ / shares	Jun. 30, 2018 $ / shares	Mar. 31, 2018 $ / shares	Dec. 31, 2017 $ / shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 $ / shares shares
Asset Acquisition [Line Items]
Equity method investments		$ 1,013,000,000				$ 926,000,000									$ 1,013,000,000	$ 926,000,000
Financing receivables – related parties		298,000,000				0									298,000,000	0
Equity method investments and other assets	$ 720,000,000
Partners' capital		$ (481,000,000)				$ (775,000,000)									$ (481,000,000)	$ (775,000,000)
Common units (in units) | shares	393,289,537
Distributions per Limited Partner unit (in dollars per share) | $ / shares		$ 0.46000	$ 0.46000	$ 0.46000	$ 0.46000	$ 0.46000	$ 0.44500	$ 0.43000	$ 0.41500	$ 0.40000	$ 0.38200	$ 0.36500	$ 0.34800	$ 0.33300	$ 1.8400	$ 1.7500	$ 1.4950
April 2020 Transaction
Asset Acquisition [Line Items]
Contract assets - related parties						$ 0										$ 0
Norco Transaction | Affiliated Entity | Valuation Technique, Discounted Cash Flow
Asset Acquisition [Line Items]
Measurement input	11.00%
Norco Transaction | April 2020 Transaction
Asset Acquisition [Line Items]
Financing receivables – related parties	$ 302,000,000
Norco Transaction | April 2020 Transaction | Affiliated Entity
Asset Acquisition [Line Items]
Contract assets - related parties	244,000,000
Consideration allocated, fair value	$ 546,000,000
Norco Transaction | April 2020 Transaction | Affiliated Entity | Revenue expected to be recognized on multi-year terminaling service contracts in place as of September 30, 2019
Asset Acquisition [Line Items]
Annual payments receivable		$ 140,000,000													$ 140,000,000
Annual payments receivable, gross		151,000,000													151,000,000
Annual payments receivable, net		$ 11,000,000													$ 11,000,000
Mattox Transaction | Affiliated Entity | Valuation Technique, Discounted Cash Flow
Asset Acquisition [Line Items]
Measurement input	14.00%
GP/IDR Restructuring | Affiliated Entity | Valuation Technique, Discounted Cash Flow
Asset Acquisition [Line Items]
Measurement input	20.00%
Preferred Units
Asset Acquisition [Line Items]
Distributions per Limited Partner unit (in dollars per share) | $ / shares	$ 0.2363														$ 0.7089
General Partner SPLC
Asset Acquisition [Line Items]
Unit distribution (in units) | shares															(4,761,012)
Units canceled (in units) | shares		0				4,761,012				4,567,588					0	4,761,012	4,567,588
Partners' capital	$ (4,000,000,000)
Economic Interest | General Partner SPLC
Asset Acquisition [Line Items]
Noncontrolling interest		2.00%													2.00%
Shell Pipeline Company L P | Limited Partner
Asset Acquisition [Line Items]
Common units (in units) | shares		269,457,304													269,457,304
Ownership interest (in percentage)															68.50%
Mattox Pipeline Company LLC (“Mattox”)
Asset Acquisition [Line Items]
Equity method investments	$ 174,000,000
Purchase And Sale Agreement | Mattox Pipeline Company LLC (“Mattox”)
Asset Acquisition [Line Items]
Equity method investment, ownership interest acquired	79.00%
Partnership Interests Restructuring Agreement | General Partner SPLC
Asset Acquisition [Line Items]
Distributions payable, amount waved	$ 20,000,000
Distribution payable, number of consecutive quarters | numberOfQuarters	4
Partnership Interests Restructuring Agreement | Limited Partner | Series A Perpetual Convertible Preferred Units
Asset Acquisition [Line Items]
Unit distribution (in units) | shares		50,782,904													50,782,904
Unit distribution (in dollars per unit) | $ / shares	$ 23.63
Partnership Interests Restructuring Agreement | Limited Partner | Common Units
Asset Acquisition [Line Items]
Unit distribution (in units) | shares	160,000,000