CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract]
Net Earnings	$ 4,947	$ 975	$ 4,507
Other Comprehensive Income (Loss), net of taxes and reclassifications to earnings [Abstract]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax	70	(57)	4
Pension and postretirement benefits	53	214	(17)
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax	(25)	39	16
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	(254)	18	(38)
Other Comprehensive Income (Loss), Net of Tax	(156)	214	(35)
Comprehensive Income	4,791	1,189	4,472
Comprehensive Income Attributable to Noncontrolling Interest	27	(32)	50
Comprehensive Income Attributable to BMS	$ 4,764	$ 1,221	$ 4,422

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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