Acquisitions (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended			12 Months Ended
	Nov. 30, 2018	Feb. 28, 2018	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Acquisitions, net of cash acquired				$ 2,451	$ 831	$ 4,332
K2M
Business Acquisition [Line Items]
Acquisitions, net of cash acquired	$ 1,380
Consideration transfered, price per share (in dollars per share)	$ 27.50
Entellus
Business Acquisition [Line Items]
Acquisitions, net of cash acquired		$ 697
Consideration transfered, price per share (in dollars per share)		$ 24.00
NOVADAQ
Business Acquisition [Line Items]
Acquisitions, net of cash acquired			$ 674