Goodwill and Intangible Assets - Additional Information (Details)	12 Months Ended
	Dec. 31, 2025 USD ($) brand	Dec. 31, 2024 USD ($) brand	Dec. 31, 2023 USD ($)
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization expense for intangible assets	$ 142,000,000	$ 153,000,000	$ 151,000,000
Estimated amortization expense for intangible assets next year	102,000,000
Estimated amortization expense for intangible assets in year two	94,000,000
Estimated amortization expense for intangible assets in year three	89,000,000
Estimated amortization expense for intangible assets in year four	87,000,000
Estimated amortization expense for intangible assets in year five	86,000,000
Goodwill impairments	$ 0	$ 0	0
Number of trademarks with fair value in excess of book value, 10% or less | brand	5
With Recognized Impairment
Goodwill and Intangible Assets Disclosure [Line Items]
Number of trademarks with fair value in excess of book value, 10% or less | brand	4
Biscuit | Europe
Goodwill and Intangible Assets Disclosure [Line Items]
Number of brands impaired | brand	2	2
Biscuit | AMEA
Goodwill and Intangible Assets Disclosure [Line Items]
Number of brands impaired | brand	1	1
Biscuit | Latin America
Goodwill and Intangible Assets Disclosure [Line Items]
Number of brands impaired | brand		1
Candy | Latin America
Goodwill and Intangible Assets Disclosure [Line Items]
Number of brands impaired | brand	1	1
Brands
Goodwill and Intangible Assets Disclosure [Line Items]
Indefinite-lived intangible asset impairment charges	$ 33,000,000	$ 153,000,000	$ 26,000,000
Impairment, Intangible Asset, Indefinite-Lived (Excluding Goodwill), Statement of Income or Comprehensive Income [Extensible Enumeration]	Restructuring, Settlement and Impairment Provisions	Restructuring, Settlement and Impairment Provisions	Restructuring, Settlement and Impairment Provisions
Book value of trademarks with fair value in excess of book value, 10% or less	$ 1,500,000,000
Customer-Related Intangible Assets
Goodwill and Intangible Assets Disclosure [Line Items]
Acquired definite-lived intangible assets, useful life	16 years