Revenues (Revenue by Segment) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Revenue	$ 46,173	$ 40,499	$ 125,629	$ 115,782
Hedging gains (losses)	(22)	119	178	364
Google
Segment Reporting Information [Line Items]
Revenue	46,017	40,225	124,990	114,931
Google | Google Search & other
Segment Reporting Information [Line Items]
Revenue	26,338	24,741	72,159	70,930
Google | YouTube ads
Segment Reporting Information [Line Items]
Revenue	5,037	3,804	12,887	10,432
Google | Google properties
Segment Reporting Information [Line Items]
Revenue	31,375	28,545	85,046	81,362
Google | Google Network Members' properties
Segment Reporting Information [Line Items]
Revenue	5,720	5,251	15,679	15,515
Google | Google advertising
Segment Reporting Information [Line Items]
Revenue	37,095	33,796	100,725	96,877
Google | Google Cloud
Segment Reporting Information [Line Items]
Revenue	3,444	2,379	9,228	6,304
Google | Google other
Segment Reporting Information [Line Items]
Revenue	5,478	4,050	15,037	11,750
Other Bets
Segment Reporting Information [Line Items]
Revenue	$ 178	$ 155	$ 461	$ 487