Composition of Certain Financial Statement Items Other Income, Costs and Expenses (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 26, 2017	Mar. 26, 2017	Mar. 27, 2016
Gain on sale of wireless spectrum		$ 0	$ 380
Proceeds from sale of wireless spectrum		0	232
Deferred payments			275
Other Operating Income (Expense) [Member]
Restructuring and restructuring-related charges	$ 25	33	129
Gain on sale of wireless spectrum			380
Gain on Disposition of Business			$ 48
Other Operating Income (Expense) [Member] \| KFTC [Member]
Foreign currency losses related to KFTC accrual	$ 53
KFTC fine		$ 921
Minimum [Member]
Deferred payments, Due date			Jan. 01, 2020
Maximum [Member]
Deferred payments, Due date			Dec. 31, 2023

Amount before tax of foreign currency transaction realized and unrealized loss recognized in the income statement.

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Amount of gain (loss) on sale or disposal of intangible assets.

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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

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The cash inflow from disposal of asset without physical form usually arising from contractual or other legal rights, excluding goodwill.

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Date the receivable or note with imputed interest is due, in CCYY-MM-DD format.

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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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