Sale of Accounts Receivable - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Oct. 01, 2016	Sep. 30, 2016	Jul. 31, 2016	Apr. 02, 2016
Receivables Sales Agreement | Other Income (Expense), Net
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gain (Loss) on Sale of Accounts Receivable	$ 3
Receivables Sales Agreement | Increase To Revolving Credit
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfers of Accounts Receivable Agreements				$ 350
Receivables Sales Agreement | Maximum
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfers of Accounts Receivable Agreements	550
Receivables Sales Agreement | Sold And Outstanding
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	546
Receivables Sales Agreement | Sold Since Inception
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	1,000
Kellogg Funding Company Program
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfers of Accounts Receivable Agreements			$ 200
Cash Proceeds Received for Assets Derecognized	222
Deferred Purchase Price	38
Kellogg Funding Company Program | Maximum
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfers of Accounts Receivable Agreements		$ 400
Kellogg Funding Company Program | Sold And Outstanding
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	260
Kellogg Funding Company Program | Sold Since Inception
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	341
Kellogg Foreign Subsidiaries Other Program
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	$ 33