Income Taxes - Reconciliation and Deferred Tax Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Examination [Line Items]
Income before tax	$ 1,623	$ 1,417	$ 721
Partnership earnings not subject to Canadian tax	(1,136)	(686)	(370)
Partnership earnings subject to Canadian tax	$ 487	$ 731	$ 351
Canadian federal and provincial corporate tax rate	24.00%	24.00%	24.00%
Income tax expense at statutory rate	$ 117	$ 175	$ 84
Canadian permanent differences	2	13	(13)
State income tax	2	1	2
Total income tax expense	121	189	$ 73
Deferred tax assets:
Lease liabilities	40	45
Other	45	16
Total deferred tax assets	85	61
Deferred tax liabilities:
Property and equipment in excess of tax values	(573)	(515)
Derivative instruments	(6)	(46)
Lease assets	(38)	(42)
Other	(3)	(3)
Total deferred tax liabilities	(620)	(606)
Net deferred tax liabilities	(535)	(545)
Other long-term liabilities and deferred credits
Deferred tax liabilities:
Other long-term liabilities and deferred credits	$ (535)	$ (545)