Goodwill (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Changes in carrying amount of goodwill
Goodwill, balance at beginning of period	$ 9,764,000,000	$ 9,762,000,000
Other	1,000,000	2,000,000
Goodwill, balance at end of period	9,765,000,000	9,764,000,000
Accumulated impairment losses	0	0	$ 0
Activision
Changes in carrying amount of goodwill
Goodwill, balance at beginning of period	6,898,000,000	6,897,000,000
Other	1,000,000	1,000,000
Goodwill, balance at end of period	6,899,000,000	6,898,000,000
Blizzard
Changes in carrying amount of goodwill
Goodwill, balance at beginning of period	190,000,000	190,000,000
Other	0	0
Goodwill, balance at end of period	190,000,000	190,000,000
King
Changes in carrying amount of goodwill
Goodwill, balance at beginning of period	2,676,000,000	2,675,000,000
Other	0	1,000,000
Goodwill, balance at end of period	$ 2,676,000,000	$ 2,676,000,000