Inventories (Details) - USD ($) $ in Millions	Oct. 01, 2017	Jan. 01, 2017
Summary of Inventories
Raw materials and supplies	$ 1,141	$ 952
Goods in process	2,388	2,185
Finished goods	5,992	5,007
Total inventories	9,521	$ 8,144
Codman Neurosurgery [Member] \| Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Inventory [Line Items]
Disposal Group, Including Discontinued Operation, Inventory, Current	$ 63

Amount classified as inventory attributable to disposal group, expected to be disposed of within one year or the normal operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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