Business Segments - Segment information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Business Segment Information
Net sales	$ 7,991	$ 8,152	$ 24,025	$ 24,820
Operating Income	2,011	2,016	4,849	5,424
Assets	42,550		42,550		$ 36,500
Depreciation and amortization			1,130	1,117
Capital expenditures			1,161	1,046
Business Segments. | Safety and Industrial
Business Segment Information
Net sales	2,849	3,021	8,796	9,542
Operating Income	765	697	2,062	2,753
Business Segments. | Transportation and Electronics
Business Segment Information
Net sales	2,503	2,619	7,312	7,665
Operating Income	631	726	1,746	2,051
Business Segments. | Health Care
Business Segment Information
Net sales	1,721	1,643	5,290	5,118
Operating Income	459	475	1,406	1,443
Business Segments. | Consumer
Business Segment Information
Net sales	1,324	1,302	3,821	3,819
Operating Income	308	300	809	811
Corporate and Unallocated
Business Segment Information
Net sales	28	35	98	47
Operating Income	(40)	(57)	(858)	(1,293)
Elimination of Dual Credit
Business Segment Information
Net sales	(434)	(468)	(1,292)	(1,371)
Operating Income	$ (112)	$ (125)	$ (316)	$ (341)