Accumulated Other Comprehensive Loss Attributable to Pepsico (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Currency translation adjustment	$ (11,940)	$ (11,290)	$ (11,918)	$ (10,277)
Cash flow hedges, net of tax	4	(3)	87	47
Unamortized pension and retiree medical, net of tax (b)	(3,520)	(2,988)	(3,271)	(2,804)
Other	(20)	(19)	(17)	(23)
Accumulated other comprehensive loss attributable to PepsiCo	(15,476)	(14,300)	(15,119)	(13,057)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax	(710)	636	(1,620)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax	10	(117)	50
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	(676)	379	(595)
Other Comprehensive Income, Other, Before Tax	(1)	(2)	6
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	(1,377)	896	(2,159)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss), before Reclassification and Tax	(710)	636	(1,664)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	126	(131)	(61)
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax	(1,141)	(89)	(813)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(1)	(2)	6
OCI, before Reclassifications, before Tax, Attributable to Parent	(1,726)	414	(2,532)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax	0	0	44
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	(116)	14	111
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax	465	468	218
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	0	0	0
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	349	482	373
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax	60	(8)	(21)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax	(3)	27	(10)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	144	(96)	128
Other Comprehensive Income, Other, Taxes	0	0	0
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	201	(77)	97
Net of taxes decrease to opening balance of accumulated other comprehensive loss attributable to Pepsico	$ 1,514	$ 1,370	$ 1,466	$ 1,338