Contingencies and Certain Commitments (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions			1 Months Ended
	Mar. 14, 2018	Mar. 12, 2018	Apr. 30, 2018	Apr. 01, 2018
Accelerated Share Repurchases [Line Items]
Share repurchase agreement, amount		$ 4,000
Accelerated share repurchases, cash paid	$ 4,000
Shares repurchased	87
Shares repurchased, price per share (in dollars per share)	$ 36.61
Shares received in initial delivery, percentage of agreement amount		80.00%
Remaining authorized repurchase amount				$ 10,300
Subsequent Event [Member] | Mylotarg [Member]
Accelerated Share Repurchases [Line Items]
Term over which additional fixed payments are to be made			10 years
Research arrangement, fixed payment obligation			$ 301