DISCONTINUED OPERATIONS - Major Classes of Line Items in Income From Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Other operating income, net	$ (48)	$ (5)	$ (140)	$ (9)
Operating income	172	155	421	449
Interest expense, net	58	87	180	251
Other (income) expense, net	(7)	(1)	(10)	(34)
Income (loss) from discontinued operations, net of tax	5	83	36	(290)
Less: Net income attributable to noncontrolling interests included in discontinued operations	0	4	0	9
Income (loss) from discontinued operations attributable to Baxter stockholders	5	79	36	(299)
Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	0	1,155	352	3,375
Cost of sales	0	731	206	2,125
Gross margin	0	424	146	1,250
Selling, general and administrative expenses	0	278	116	874
Research and development expenses	0	41	16	140
Goodwill impairment	0	0	0	430
Other operating income, net	0	(1)	0	(1)
Operating income	0	106	14	(193)
Interest expense, net	0	1	13	0
Other (income) expense, net	0	(8)	7	(2)
Income (loss) from discontinued operations before gain on disposition and income taxes	0	113	(6)	(191)
Gain (loss) on disposition	(55)	0	115	0
Income tax expense (benefit)	60	(30)	(73)	(99)
Income (loss) from discontinued operations, net of tax	5	83	36	(290)
Less: Net income attributable to noncontrolling interests included in discontinued operations	0	4	0	9
Income (loss) from discontinued operations attributable to Baxter stockholders	5	$ 79	$ 36	$ (299)
Discontinued Operations, Disposed of by Sale | Tax Years 2021 Through 2025
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense (benefit)	$ 41