Segment Reporting - Net Revenues by Product Category (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Segment Reporting Information [Line Items]
Total net revenues	$ 8,984	$ 8,343	$ 18,297	$ 17,633
Biscuits & Baked Snacks
Segment Reporting Information [Line Items]
Total net revenues	4,575	4,357	8,906	8,656
Chocolate
Segment Reporting Information [Line Items]
Total net revenues	2,661	2,233	5,843	5,247
Gum & Candy
Segment Reporting Information [Line Items]
Total net revenues	950	957	1,920	2,013
Beverages
Segment Reporting Information [Line Items]
Total net revenues	227	266	524	619
Cheese & Grocery
Segment Reporting Information [Line Items]
Total net revenues	571	530	1,104	1,098
Latin America
Segment Reporting Information [Line Items]
Total net revenues	1,194	1,232	2,397	2,551
Latin America \| Biscuits & Baked Snacks
Segment Reporting Information [Line Items]
Total net revenues	295	310	582	596
Latin America \| Chocolate
Segment Reporting Information [Line Items]
Total net revenues	345	304	714	686
Latin America \| Gum & Candy
Segment Reporting Information [Line Items]
Total net revenues	361	381	702	774
Latin America \| Beverages
Segment Reporting Information [Line Items]
Total net revenues	79	114	175	244
Latin America \| Cheese & Grocery
Segment Reporting Information [Line Items]
Total net revenues	114	123	224	251
AMEA
Segment Reporting Information [Line Items]
Total net revenues	1,821	1,587	3,837	3,537
AMEA \| Biscuits & Baked Snacks
Segment Reporting Information [Line Items]
Total net revenues	686	560	1,422	1,204
AMEA \| Chocolate
Segment Reporting Information [Line Items]
Total net revenues	657	579	1,430	1,350
AMEA \| Gum & Candy
Segment Reporting Information [Line Items]
Total net revenues	261	237	504	471
AMEA \| Beverages
Segment Reporting Information [Line Items]
Total net revenues	122	124	286	313
AMEA \| Cheese & Grocery
Segment Reporting Information [Line Items]
Total net revenues	95	87	195	199
Europe
Segment Reporting Information [Line Items]
Total net revenues	3,412	2,874	6,962	6,242
Europe \| Biscuits & Baked Snacks
Segment Reporting Information [Line Items]
Total net revenues	1,289	1,093	2,377	2,123
Europe \| Chocolate
Segment Reporting Information [Line Items]
Total net revenues	1,589	1,293	3,529	3,063
Europe \| Gum & Candy
Segment Reporting Information [Line Items]
Total net revenues	146	140	308	346
Europe \| Beverages
Segment Reporting Information [Line Items]
Total net revenues	26	28	63	62
Europe \| Cheese & Grocery
Segment Reporting Information [Line Items]
Total net revenues	362	320	685	648
North America
Segment Reporting Information [Line Items]
Total net revenues	2,557	2,650	5,101	5,303
North America \| Biscuits & Baked Snacks
Segment Reporting Information [Line Items]
Total net revenues	2,305	2,394	4,525	4,733
North America \| Chocolate
Segment Reporting Information [Line Items]
Total net revenues	70	57	170	148
North America \| Gum & Candy
Segment Reporting Information [Line Items]
Total net revenues	182	199	406	422
North America \| Beverages
Segment Reporting Information [Line Items]
Total net revenues	0	0	0	0
North America \| Cheese & Grocery
Segment Reporting Information [Line Items]
Total net revenues	$ 0	$ 0	$ 0	$ 0