Debt (Details) $ in Millions, $ in Millions		3 Months Ended		9 Months Ended
	Jun. 25, 2024 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2024 CAD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2024 CAD ($)	Sep. 30, 2024 CAD ($)	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Extinguishment of debt, principal amount		$ 66	$ 90	$ 176	$ 241
Gain on extinguishment of senior notes			$ 6		22
Commercial paper borrowings							$ 800
5.41% Senior Secured Notes | Senior Notes
Debt Instrument [Line Items]
Repayment of note				$ 48	$ 66
Interest rate		5.41%		5.41%		5.41%
Five-year Amended and Restated Revolving Credit Facility | Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Note term	5 years
Maximum borrowing capacity (up to)	$ 1,100
Two-year Amended and Restated Revolving Credit Facility | Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Note term	2 years
Maximum borrowing capacity (up to)	$ 1,100
Commercial Paper | Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity (up to)		$ 1,500		$ 1,500
Commercial paper borrowings		$ 280		$ 280		$ 378
Weighted average interest rate		5.15%		5.15%		5.15%	5.59%
Second Amended and Restated Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity (up to)		$ 2,200		$ 2,200