CONDENSED CONSOLIDATED BALANCE SHEETS (PARENTHETICAL) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts, loans and interest receivable	$ 754	$ 258
Common stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	4,000,000,000	4,000,000,000
Common stock, shares outstanding (in shares)	1,173,000,000	1,173,000,000
Preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	100,000,000	100,000,000
Treasury stock, shares (in shares)	113,000,000	105,000,000