EARNINGS PER SHARE (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Earnings Per Share [Abstract]
Net Earnings Attributable to BMS	$ 925	$ (711)	$ 645	$ 1,101	$ 852	$ 969	$ 902	$ 986	$ 1,960	$ 3,709	$ 3,102
Earnings attributable to unvested restricted shares									(1)	(8)	(12)
Net Earnings Attributable to BMS common shareholders									$ 1,959	$ 3,701	$ 3,090
Earnings per share - basic	$ 0.56	$ (0.43)	$ 0.38	$ 0.65	$ 0.50	$ 0.57	$ 0.53	$ 0.58	$ 1.17	$ 2.18	$ 1.80
Weighted-average common shares outstanding - basic									1,670	1,700	1,713
Contingently convertible debt common stock equivalents									1	1	1
Incremental shares attributable to share-based compensation plans									17	16	13
Weighted-average common shares outstanding - diluted									1,688	1,717	1,727
Earnings per share - diluted	$ 0.56	$ (0.43)	$ 0.38	$ 0.64	$ 0.50	$ 0.56	$ 0.52	$ 0.57	$ 1.16	$ 2.16	$ 1.79
Anti-dilutive weighted-average equivalent shares - stock incentive plans									2	13	51