Venezuela (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2016	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Foreign Currency [Line Items]
Venezuela Deconsolidation Loss Amount		$ 0	$ 0	$ (72)
Venezuela deconsolidation loss related to CTA, net of tax		$ 0	$ 0	$ 63
Other Income (Expense), Net
Foreign Currency [Line Items]
Venezuela Deconsolidation Loss Amount	$ (72)

The amount of the loss recognized by the parent and included in its attributable portion of net income for the period due to deconsolidation of a subsidiary or derecognition of a group of assets. The gain (loss) recognized and included in the net income attributable to the parent for the period is generally computed as the difference between: (a) the aggregate of: (1) the fair value of any consideration received; (2) the fair value of any retained noncontrolling investment in the former subsidiary at the date the subsidiary was deconsolidated; and (3) the carrying amount of any noncontrolling interest in the former subsidiary (including any accumulated other comprehensive income attributable to the noncontrolling interest) at the date the subsidiary was deconsolidated and (b) the carrying amount of the former subsidiary's assets and liabilities

No definition available.

Name:	k_VenezuelaDeconsolidationLossAmount
Namespace Prefix:	k_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration