Investments in Equity Securities (Investment in AB InBev Narrative) (Details) shares in Millions, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Mar. 31, 2019 € / shares	Dec. 31, 2018 € / shares
Schedule of Equity Method Investments [Line Items]
Investments in equity securities | $	$ 32,015	$ 30,496
AB InBev [Member]
Schedule of Equity Method Investments [Line Items]
Derivative instrument, number of shares hedged (in shares) | shares		92.4
AB InBev [Member]
Schedule of Equity Method Investments [Line Items]
Number of ordinary shares owned (in shares) | shares	12.0
Equity method investment, ownership percentage	10.10%
Number of restricted shares owned (in shares) | shares	185.0
Share price (in Euro per share) | € / shares			€ 74.76	€ 57.70
Fair value of equity investment | $	$ 16,600	$ 13,100
Investments in equity securities | $	$ 17,476	$ 17,696
Difference between carrying amount and underlying equity, percentage	5.00%	26.00%