Comparison of income tax expense at the Statutory rate and Company's tax rate.

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Effective income tax rate reconciliation related to domestic tax on international income.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the income tax rates.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to disposition of asset. Includes, but is not limited to, intra-entity transfer of asset other than inventory.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Income Taxes - Comparison of Income Taxes at Statutory Rate and Company's Effective Tax Rate (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Oct. 01, 2017	Jul. 02, 2017	Apr. 02, 2017	Jan. 01, 2017	Oct. 02, 2016	Jul. 03, 2016	Apr. 03, 2016	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Comparison Of Income Tax Expense At Statutory Rate And Company's Tax Rate Abstract
U.S.									$ 4,865	$ 7,457	$ 8,179
International									12,808	12,346	11,017
Earnings before provision for taxes on income	$ 2,560	$ 4,790	$ 4,748	$ 5,575	$ 4,324	$ 5,281	$ 4,904	$ 5,294	$ 17,673	$ 19,803	$ 19,196
Tax Rates:
U.S. statutory rate									35.00%	35.00%	35.00%
International operations (1)									(12.80%)	(17.20%)	(15.40%)
Research and orphan drug tax credits									(0.40%)	(0.40%)	(0.20%)
U.S. state and local									0.60%	(0.10%)	0.40%
U.S. manufacturing deduction									(0.80%)	(0.60%)	(0.60%)
U.S. tax on international income									0.70%	1.30%	0.20%
Tax benefits on share based compensation									(2.10%)	(1.80%)	(0.00%)
U.S. tax benefit on asset/business disposals									(0.80%)	0.00%	0.00%
All other									(0.10%)	0.30%	0.30%
TCJA impact									73.30%	0.00%	0.00%
Effective tax rate									92.60%	16.50%	19.70%
State and Local Jurisdiction
Tax Rates:
TCJA impact									0.60%
Administration of the Treasury, Belgium [Member]
Tax Rates:
TCJA impact									3.40%