Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disaggregation of Revenue [Line Items]
Revenues from customers	$ 3,100	$ 4,992	$ 6,545	$ 9,081
Leasing services	346	331	676	645
Derivatives adjustments on commodity sales	28	(202)	114	(343)
Other	27	30	54	61
Total other revenues	401	159	844	363
Total revenues	3,501	5,151	7,389	9,444
Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Total revenues	1,987	3,363	4,450	6,156
Products Pipelines
Disaggregation of Revenue [Line Items]
Total revenues	735	996	1,403	1,762
Terminals
Disaggregation of Revenue [Line Items]
Total revenues	477	449	937	878
CO2
Disaggregation of Revenue [Line Items]
Total revenues	302	343	599	648
Operating Segments | Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	1,814	3,303	4,040	6,023
Leasing services	120	118	237	235
Derivatives adjustments on commodity sales	40	(81)	147	(120)
Other	17	16	33	31
Total other revenues	177	53	417	146
Total revenues	1,991	3,356	4,457	6,169
Operating Segments | Products Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	675	942	1,291	1,661
Leasing services	52	49	99	93
Derivatives adjustments on commodity sales	2	0	1	(3)
Other	6	5	12	11
Total other revenues	60	54	112	101
Total revenues	735	996	1,403	1,762
Operating Segments | Terminals
Disaggregation of Revenue [Line Items]
Revenues from customers	315	301	624	591
Leasing services	163	149	315	289
Derivatives adjustments on commodity sales	0	0	0	0
Other	0	0	0	0
Total other revenues	163	149	315	289
Total revenues	478	450	939	880
Operating Segments | CO2
Disaggregation of Revenue [Line Items]
Revenues from customers	301	440	599	821
Leasing services	11	15	25	28
Derivatives adjustments on commodity sales	(14)	(121)	(34)	(220)
Other	4	9	9	19
Total other revenues	1	(97)	0	(173)
Total revenues	302	343	599	648
Corporate and intersegment eliminations
Disaggregation of Revenue [Line Items]
Revenues from customers	(5)	6	(9)	(15)
Leasing services	0	0	0	0
Derivatives adjustments on commodity sales	0	0	0	0
Other	0	0	0	0
Total other revenues	0	0	0	0
Total revenues	(5)	6	(9)	(15)
Firm services
Disaggregation of Revenue [Line Items]
Revenues from customers	1,107	1,107	2,270	2,292
Firm services | Operating Segments | Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	849	849	1,766	1,788
Firm services | Operating Segments | Products Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	49	60	89	119
Firm services | Operating Segments | Terminals
Disaggregation of Revenue [Line Items]
Revenues from customers	208	198	415	386
Firm services | Operating Segments | CO2
Disaggregation of Revenue [Line Items]
Revenues from customers	1	1	1	1
Firm services | Corporate and intersegment eliminations
Disaggregation of Revenue [Line Items]
Revenues from customers	0	(1)	(1)	(2)
Fee-based services
Disaggregation of Revenue [Line Items]
Revenues from customers	602	583	1,186	1,141
Fee-based services | Operating Segments | Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	248	234	484	447
Fee-based services | Operating Segments | Products Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	246	242	486	476
Fee-based services | Operating Segments | Terminals
Disaggregation of Revenue [Line Items]
Revenues from customers	98	96	196	194
Fee-based services | Operating Segments | CO2
Disaggregation of Revenue [Line Items]
Revenues from customers	10	11	20	24
Fee-based services | Corporate and intersegment eliminations
Disaggregation of Revenue [Line Items]
Revenues from customers	0	0	0	0
Total services
Disaggregation of Revenue [Line Items]
Revenues from customers	1,709	1,690	3,456	3,433
Total services | Operating Segments | Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	1,097	1,083	2,250	2,235
Total services | Operating Segments | Products Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	295	302	575	595
Total services | Operating Segments | Terminals
Disaggregation of Revenue [Line Items]
Revenues from customers	306	294	611	580
Total services | Operating Segments | CO2
Disaggregation of Revenue [Line Items]
Revenues from customers	11	12	21	25
Total services | Corporate and intersegment eliminations
Disaggregation of Revenue [Line Items]
Revenues from customers	0	(1)	(1)	(2)
Natural gas sales
Disaggregation of Revenue [Line Items]
Revenues from customers	495	1,828	1,312	3,070
Natural gas sales | Operating Segments | Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	484	1,810	1,283	3,036
Natural gas sales | Operating Segments | Products Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	0	0	0	0
Natural gas sales | Operating Segments | Terminals
Disaggregation of Revenue [Line Items]
Revenues from customers	0	0	0	0
Natural gas sales | Operating Segments | CO2
Disaggregation of Revenue [Line Items]
Revenues from customers	13	24	33	44
Natural gas sales | Corporate and intersegment eliminations
Disaggregation of Revenue [Line Items]
Revenues from customers	(2)	(6)	(4)	(10)
Product sales
Disaggregation of Revenue [Line Items]
Revenues from customers	896	1,474	1,777	2,578
Product sales | Operating Segments | Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	233	410	507	752
Product sales | Operating Segments | Products Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	380	640	716	1,066
Product sales | Operating Segments | Terminals
Disaggregation of Revenue [Line Items]
Revenues from customers	9	7	13	11
Product sales | Operating Segments | CO2
Disaggregation of Revenue [Line Items]
Revenues from customers	277	404	545	752
Product sales | Corporate and intersegment eliminations
Disaggregation of Revenue [Line Items]
Revenues from customers	(3)	13	(4)	(3)
Total commodity sales
Disaggregation of Revenue [Line Items]
Revenues from customers	1,391	3,302	3,089	5,648
Total revenues	1,421	3,100	3,206	5,308
Total commodity sales | Operating Segments | Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	717	2,220	1,790	3,788
Total commodity sales | Operating Segments | Products Pipelines
Disaggregation of Revenue [Line Items]
Revenues from customers	380	640	716	1,066
Total commodity sales | Operating Segments | Terminals
Disaggregation of Revenue [Line Items]
Revenues from customers	9	7	13	11
Total commodity sales | Operating Segments | CO2
Disaggregation of Revenue [Line Items]
Revenues from customers	290	428	578	796
Total commodity sales | Corporate and intersegment eliminations
Disaggregation of Revenue [Line Items]
Revenues from customers	$ (5)	$ 7	$ (8)	$ (13)