EQUITY (Changes in Equity) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Jan. 01, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Equity [Line Items]
Common Stock, Dividends, Per Share, Declared	$ 0	$ 0.40
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Value, Issued, Balance at Beginning of Period	$ 221
Common Stock, Value, Issued, Balance at End of Period	221
Capital in Excess of Par Value of Stock, Balance at Beginning of Period	2,081
Capital in Excess of Par Value of Stock, Balance at End of Period	2,103
Accumulated Other Comprehensive Loss, Balance at Beginning of Period	(2,762)
Other Comprehensive Income/(Loss)	118	$ 89
Accumulated Other Comprehensive Loss, Balance at End of Period	(2,644)
Retained Earnings, Balance at Beginning of Period	34,065
Net Earnings Attributable to BMS	1,710	1,486
Retained Earnings, Balance at End of Period	35,109
Cost of Treasury Stock, Balance at Beginning of Period	(19,574)
Cost of Treasury Stock, Balance at End of Period	(19,571)
Noncontrolling interest, Balance at Beginning of Period	96
Net Income (Loss) Attributable to Noncontrolling Interest	(5)	$ (9)
Noncontrolling interest, Balance at End of Period	$ 99
Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares Issued, Balance at Beginning of Period	2,208	2,208
Common Stock, Shares Issued, Balance at End of Period	2,208	2,208
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 [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital in Excess of Par Value of Stock, Balance at Beginning of Period	2,081	1,898
Stockholders' Equity, Other	22	18
Capital in Excess of Par Value of Stock, Balance at End of Period	2,103	1,916
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated Other Comprehensive Loss, Balance at Beginning of Period	(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)	118	89
Accumulated Other Comprehensive Loss, Balance at End of Period	(2,644)	(2,234)
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	34,065	31,160
Net Earnings Attributable to BMS	1,710	1,486
Cash dividends declared	(671)	(655)
Retained Earnings, Balance at End of Period	$ 35,109	$ 32,323
Treasury Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury Stock, Shares, Balance at Beginning of Period	576	575
Stock repurchase program, Shares		3
Shares Paid for Tax Withholding for Share Based Compensation	(4)	(4)
Treasury Stock, Shares, Balance at End of Period	572	574
Cost of Treasury Stock, Balance at Beginning of Period	$ (19,574)	$ (19,249)
Stock repurchase program, Cost		(166)
Employee stock compensation plans, Cost	3	(18)
Cost of Treasury Stock, Balance at End of Period	(19,571)	(19,433)
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Noncontrolling interest, Balance at Beginning of Period	96	106
Net Income (Loss) Attributable to Noncontrolling Interest	5	9
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(2)	(2)
Noncontrolling interest, Balance at End of Period	$ 99	$ 113