INCOME TAXES (Reserve for unrecognized tax benefits, interest and penalties) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Balance at beginning of year	$ 404	$ 390	$ 101
Additions:
Prior year tax positions	73	100	302
Current year tax positions	11	14	6
Decreases:
Prior year tax positions	(75)	(86)	(1)
Settlements with taxing authorities	(37)	(9)	(17)
Lapse of statute of limitations	0	(5)	(1)
Balance at end of year	$ 376	$ 404	$ 390