Debt (Details) $ in Millions, $ in Millions		1 Months Ended		3 Months Ended		6 Months Ended
	Jun. 25, 2024 USD ($)	Jul. 30, 2024 USD ($)	Jul. 30, 2024 CAD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2024 CAD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2024 CAD ($)	Jun. 30, 2024 CAD ($)	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Early repayment of senior notes				$ 110	$ 151	$ 110	$ 151
Gain on extinguishment of senior notes					$ 16		16
Commercial paper borrowings									$ 800
Senior Notes | Subsequent Event
Debt Instrument [Line Items]
Repayment of note		$ 26	$ 35
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				$ 536		$ 536		$ 734
Weighted average interest rate				5.53%		5.53%		5.53%	5.59%
Second Amended and Restated Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity (up to)				$ 2,200		$ 2,200