Accumulated Other Comprehensive Income - Summary of Amounts Reclassification from AOCI to Net Income (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income, net	$ (9)	$ 1	$ 8	$ 45
Income tax expense (benefit)	106	(146)	163	(37)
Cost of sales	1,621	1,529	4,860	4,690
Net income attributable to Baxter stockholders	369	518	1,024	1,241
Amounts reclassified from AOCI
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income attributable to Baxter stockholders	(2)	(14)	(14)	(51)
Amortization of pension and OPEB items | Amounts reclassified from AOCI
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income, net	(8)	(18)	(23)	(54)
Income tax expense (benefit)	4	4	6	10
Net income attributable to Baxter stockholders	(4)	(14)	(17)	(44)
Hedging activities | Amounts reclassified from AOCI
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense (benefit)	0	1	0	4
Net income attributable to Baxter stockholders	2	0	3	(7)
Hedging activities | Foreign exchange contracts | Amounts reclassified from AOCI
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of sales	$ 2	$ (1)	$ 3	$ (11)