Quarterly Financial Data (unaudited) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions				1 Months Ended	3 Months Ended								12 Months Ended
	May. 15, 2015	May. 15, 2014	Jan. 04, 2013	Oct. 31, 2014	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net revenues					$ 6,400	$ 5,944	$ 5,475	$ 5,040	$ 5,452	$ 5,019	$ 4,926	$ 4,563	$ 22,859	$ 19,960	$ 18,790
Gross margin					4,925	4,777	4,559	4,098	4,333	3,925	3,813	3,463
Net earnings					$ 1,517	$ 1,239	$ 1,366	$ 1,022	$ (810)	$ 506	$ 1,098	$ 980	$ 5,144	$ 1,774	$ 4,128
Basic earnings per share (in dollars per share)					$ 0.93	$ 0.75	$ 0.84	$ 0.64	$ (0.51)	$ 0.32	$ 0.69	$ 0.61	$ 3.15	$ 1.11	$ 2.58
Diluted earnings per share (in dollars per share)					0.92	0.74	0.83	0.63	(0.51)	0.31	0.68	0.61	3.13	1.10	2.56
Cash dividends declared per common share (in dollars per share)			$ 0.40		$ 0.57	$ 0.51	$ 0.51	$ 0.51	$ 0.49	$ 0.42	$ 0.42	$ 0.42	$ 2.10	$ 1.75	$ 2.00	[1]
Royalty revenue														$ 81
Milestone revenue													$ 40
Increase litigation reserves					$ 101
Cash Dividends
Anti-dilutive securities excluded from the computation of earnings per common share (in shares)									36
C2N Diagnostics
Initial upfront payment								$ 100
HCV
Payments to collaborators											$ 40
Rare Pediatric Disease Priority Review Voucher From United Therapeutics Corporation
Research and development expense						$ 350
Calico Life Sciences LLC
Initial upfront payment													500	250
Research and development expense									$ 500
Payments to collaborators										$ 250
Infinity Pharmaceuticals Inc
Payments to collaborators						83				173
Dividend Paid Quarter One
Cash Dividends
Date declared								Feb. 19, 2015				Feb. 20, 2014
Dividends paid (in dollars per share)	$ 0.51	$ 0.42
Pharmacyclics Inc
Net revenues													$ 774
Acquisition-related and financing-related costs					$ 68	$ 85	$ 215	$ 41
Shire plc
Foreign exchange loss associated with forward contracts								$ (170)						(490)
Acquisition-related and financing-related costs														$ 1,800
Break fee				$ 1,600					$ 1,600
Shire plc | Calico Life Sciences LLC
Payments to collaborators										$ 172

[1] On January 4, 2013, a cash dividend of $0.40 per share of common stock was declared from pre-separation earnings and was recorded as a reduction of additional paid-in capital.