Business Segments - Segment information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Business Segment Information
Net sales	$ 8,171	$ 8,390	$ 16,034	$ 16,668
Operating Income	1,702	2,401	2,838	3,408
Assets	38,969		38,969		$ 36,500
Depreciation and amortization			751	762
Capital expenditures			812	669
Business Segments. \| Safety and Industrial
Business Segment Information
Net sales	2,961	3,253	5,947	6,521
Operating Income	653	1,285	1,297	2,056
Business Segments. \| Transportation and Electronics
Business Segment Information
Net sales	2,452	2,527	4,809	5,046
Operating Income	592	669	1,115	1,325
Business Segments. \| Health Care
Business Segment Information
Net sales	1,831	1,730	3,569	3,475
Operating Income	483	470	947	968
Business Segments. \| Consumer
Business Segment Information
Net sales	1,303	1,309	2,497	2,517
Operating Income	268	279	501	511
Corporate and Unallocated
Business Segment Information
Net sales	48	12	70	12
Operating Income	(193)	(200)	(818)	(1,236)
Elimination of Dual Credit
Business Segment Information
Net sales	(424)	(441)	(858)	(903)
Operating Income	$ (101)	$ (102)	$ (204)	$ (216)

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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