FAIR VALUE MEASUREMENTS (Details - Assets measured at fair value on a non-recurring basis at the time of impairment and the related impairment charges recorded during the periods presented) - Fair value on a non-recurring basis - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Fair Value Assets Impairment Charges Measured on Nonrecurring Basis [Domain]
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Impairment Charges	$ 26	$ 62	$ 75	$ 90
Other investments
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Impairment Charges	17	61	58	89
Other assets
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Impairment Charges	9	$ 1	17	$ 1
Level 1 | Fair Value Assets Impairment Charges Measured on Nonrecurring Basis [Domain]
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	0		0		$ 0
Level 1 | Other investments
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	0		0		0
Level 1 | Other assets
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	0		0		0
Level 2 | Fair Value Assets Impairment Charges Measured on Nonrecurring Basis [Domain]
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	0		0		0
Level 2 | Other investments
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	0		0		0
Level 2 | Other assets
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	0		0		0
Level 3 | Fair Value Assets Impairment Charges Measured on Nonrecurring Basis [Domain]
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	260		260		326
Level 3 | Other investments
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	259		259		315
Level 3 | Other assets
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	1		1		11
Total Fair Value | Fair Value Assets Impairment Charges Measured on Nonrecurring Basis [Domain]
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	260		260		326
Total Fair Value | Other investments
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	259		259		315
Total Fair Value | Other assets
Fair Value Assets Measured on Nonrecurring Basis [Line Items]
Fair Value	$ 1		$ 1		$ 11