EARNINGS/(LOSS) PER SHARE (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Net Earnings/(Loss) Attributable to BMS	$ 692	$ (711)	$ 1,837	$ 1,035
Earnings attributable to unvested restricted shares				(1)
Net Earnings Attributable to BMS common shareholders	$ 692	$ (711)	$ 1,837	$ 1,034
Earnings/(Loss) per share - basic	$ 0.42	$ (0.43)	$ 1.12	$ 0.62
Weighted-average common shares outstanding - basic	1,646	1,666	1,643	1,679
Contingently convertible debt common stock equivalents	1		1	1
Incremental shares attributable to share-based compensation plans	15		15	17
Weighted-average common shares outstanding - diluted	1,662	1,666	1,659	1,697
Earnings/(Loss) per share - diluted	$ 0.42	$ (0.43)	$ 1.11	$ 0.61
Anti-dilutive weighted-average equivalent shares - stock incentive plans				2
Contingently convertible debt common stock equivalents and incremental shares attributable to share-based compensation plans excluded from the per share calculation		17