Acquisitions (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Acquisitions, net of cash acquired											$ 831	$ 4,332	$ 153
Net sales			$ 3,471	$ 3,006	$ 3,012	$ 2,955	$ 3,157	$ 2,833	$ 2,840	$ 2,495	$ 12,444	11,325	$ 9,946
Entellus Medical, Inc.
Business Acquisition [Line Items]
Net sales												$ 75
Entellus Medical, Inc.
Business Acquisition [Line Items]
Acquisitions, net of cash acquired	$ 662
Business acquisition, share price	$ 24.00		$ 24.00								$ 24.00
NOVADAQ Acquisition
Business Acquisition [Line Items]
Acquisitions, net of cash acquired		$ 716