EQUITY (Changes in Equity) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Jan. 01, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Equity [Line Items]
Common Stock, Dividends, Per Share, Declared	$ 0.41		$ 0.40		$ 0.41	$ 0.40
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Value, Issued, Balance at Beginning of Period		$ 221			$ 221
Common Stock, Value, Issued, Balance at End of Period	$ 221				221
Capital in Excess of Par Value of Stock, Balance at Beginning of Period		2,081			2,081
Capital in Excess of Par Value of Stock, Balance at End of Period	2,150				2,150
Accumulated Other Comprehensive Loss, Balance at Beginning of Period		(2,762)			(2,762)
Other Comprehensive Income/(Loss)	23		$ (100)		141	$ (11)
Accumulated Other Comprehensive Loss, Balance at End of Period	(2,621)				(2,621)
Retained Earnings, Balance at Beginning of Period		34,065			34,065
Net Earnings Attributable to BMS	1,432		373		3,142	1,859
Retained Earnings, Balance at End of Period	35,870				35,870
Cost of Treasury Stock, Balance at Beginning of Period		(19,574)			(19,574)
Cost of Treasury Stock, Balance at End of Period	(19,571)				(19,571)
Noncontrolling interest, Balance at Beginning of Period		$ 96			96
Net Income (Loss) Attributable to Noncontrolling Interest	(7)		$ (9)		(12)	$ (18)
Noncontrolling interest, Balance at End of Period	$ 102				$ 102
Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares Issued, Balance at Beginning of Period	2,208	2,208	2,208	2,208	2,208	2,208
Common Stock, Shares Issued, Balance at End of Period	2,208	2,208	2,208	2,208	2,208	2,208
Common Stock, Value, Issued, Balance at Beginning of Period	$ 221	$ 221	$ 221	$ 221	$ 221	$ 221
Common Stock, Value, Issued, Balance at End of Period	221	221	221	221	221	221
Capital in Excess of Par Value of Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital in Excess of Par Value of Stock, Balance at Beginning of Period	2,103	2,081	1,916	1,898	2,081	1,898
Stockholders' Equity, Other	47	22	50	18
Capital in Excess of Par Value of Stock, Balance at End of Period	2,150	2,103	1,966	1,916	2,150	1,966
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated Other Comprehensive Loss, Balance at Beginning of Period	(2,644)	(2,762)	(2,234)	(2,289)	(2,762)	(2,289)
Cumulative effect of an accounting change on retained earnings									$ (34)
Retained Earnings, Adjusted balance at Beginning of Period								$ (2,762)		$ (2,323)
Other Comprehensive Income/(Loss)	23	118	(100)	89
Accumulated Other Comprehensive Loss, Balance at End of Period	(2,621)	(2,644)	(2,334)	(2,234)	(2,621)	(2,334)
Retained Earnings [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of an accounting change on retained earnings							$ 5		$ 332
Retained Earnings, Adjusted balance at Beginning of Period								$ 34,070		$ 31,492
Retained Earnings, Balance at Beginning of Period	35,109	34,065	32,323	31,160	34,065	31,160
Net Earnings Attributable to BMS	1,432	1,710	373	1,486
Cash dividends declared	(671)	(671)	(652)	(655)
Retained Earnings, Balance at End of Period	$ 35,870	$ 35,109	$ 32,044	$ 32,323	$ 35,870	$ 32,044
Treasury Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury Stock, Shares, Balance at Beginning of Period	572	576	574	575	576	575
Stock repurchase program, Shares			2	3
Shares Paid for Tax Withholding for Share Based Compensation	0	(4)	0	(4)
Treasury Stock, Shares, Balance at End of Period	572	572	576	574	572	576
Cost of Treasury Stock, Balance at Beginning of Period	$ (19,571)	$ (19,574)	$ (19,433)	$ (19,249)	$ (19,574)	$ (19,249)
Stock repurchase program, Cost			(147)	(166)
Employee stock compensation plans, Cost	0	3	0	(18)
Cost of Treasury Stock, Balance at End of Period	(19,571)	(19,571)	(19,580)	(19,433)	(19,571)	(19,580)
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Noncontrolling interest, Balance at Beginning of Period	99	96	113	106	96	106
Net Income (Loss) Attributable to Noncontrolling Interest	7	5	9	9
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(4)	(2)	(21)	(2)
Noncontrolling interest, Balance at End of Period	$ 102	$ 99	$ 101	$ 113	$ 102	$ 101