STOCKHOLDERS' EQUITY - Share Repurchases (Details) - USD ($) shares in Thousands	4 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jul. 30, 2019	Nov. 28, 2018	Dec. 21, 2017	Dec. 14, 2017	Feb. 16, 2017	Feb. 14, 2017
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization					$ 3,000,000,000	$ 3,000,000,000.0	$ 3,000,000,000.0	$ 3,000,000,000	$ 2,250,000,000	$ 2,250,000,000
Shares repurchased (in shares)	3,040
Cost of repurchases	$ 750,000,000	$ 1,070,000,000	$ 1,090,000,000	$ 3,365,000,000
February 2017 Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization		$ 2,250,000,000
Shares repurchased (in shares)		0	0	9,710
Cost of repurchases		$ 0	$ 0	$ 2,250,000,000
December 2017 Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization		$ 3,000,000,000
Shares repurchased (in shares)		0	3,070	3,280
Cost of repurchases		$ 0	$ 1,024,000,000	$ 800,000,000
July 2019 Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization		$ 3,000,000,000
Shares repurchased (in shares)		3,400	0	0
Cost of repurchases		$ 1,000,000,000	$ 0	$ 0
Excluding Employee Stock Plans and ASR
Equity, Class of Treasury Stock [Line Items]
Shares repurchased (in shares)		3,400	3,070	12,990
Cost of repurchases		$ 1,000,000,000	$ 1,024,000,000	$ 3,050,000,000