Earnings per Share - Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Denominator
Number of shares used for basic EPS computation (in shares)	2,851	2,856
Basic EPS (in dollars per share)	$ 1.72	$ 0.85
Denominator
Number of shares used for diluted EPS computation (in shares)	2,868	2,869
Diluted EPS (in dollars per share)	$ 1.71	$ 0.85
Class A Common Stock
Numerator
Net income	$ 4,138	$ 2,038
Denominator
Number of shares used for basic EPS computation (in shares)	2,407	2,396
Basic EPS (in dollars per share)	$ 1.72	$ 0.85
Numerator
Net income	$ 4,138	$ 2,038
Reallocation of net income as a result of conversion of Class B to Class A common stock	764	391
Reallocation of net income to Class B common stock	0	0
Net income for diluted EPS	$ 4,902	$ 2,429
Denominator
Conversion of Class B to Class A common stock (in shares)	444	460
Weighted average effect of dilutive RSUs and employee stock options (in shares)	17	13
Number of shares used for diluted EPS computation (in shares)	2,868	2,869
Diluted EPS (in dollars per share)	$ 1.71	$ 0.85
Class B Common Stock
Numerator
Net income	$ 764	$ 391
Denominator
Number of shares used for basic EPS computation (in shares)	444	460
Basic EPS (in dollars per share)	$ 1.72	$ 0.85
Numerator
Net income	$ 764	$ 391
Reallocation of net income as a result of conversion of Class B to Class A common stock	0	0
Reallocation of net income to Class B common stock	(5)	0
Net income for diluted EPS	$ 759	$ 391
Denominator
Conversion of Class B to Class A common stock (in shares)	0	0
Weighted average effect of dilutive RSUs and employee stock options (in shares)	0	2
Number of shares used for diluted EPS computation (in shares)	444	462
Diluted EPS (in dollars per share)	$ 1.71	$ 0.85