Investments in Equity Securities (Investment in ABI Narrative) (Details) - USD ($) shares in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Fair value of equity investment	$ 11,200,000,000	$ 11,200,000,000
Equity method investment, difference between carrying amount and underlying equity	$ 14,000,000	$ 14,000,000	$ 77,000,000
ABI [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	10.00%	10.00%
Number of restricted shares owned (in shares)	185	185
Number of ordinary shares owned (in shares)	12	12
Restricted shares, lock-up period		5 years
Investments in equity securities	$ 11,237,000,000	$ 11,237,000,000	$ 16,651,000,000
Difference between carrying amount and fair value, percentage (approximately)		35.00%	17.00%
Equity method investment, impairment	$ 6,157,000,000	$ 6,157,000,000	$ 0
Equity method investment, reduction in share price, percentage	18.00%	18.00%
Equity method investment, difference between carrying amount and underlying equity	$ 5,100,000,000	$ 5,100,000,000
Fair Value, Inputs, Level 1 [Member] | ABI [Member]
Schedule of Equity Method Investments [Line Items]
Fair value of equity investment			$ 13,800,000,000