INSURANCE CONTRACTS Components of loss reserves (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018
Insurance contracts [Abstract]
Case reserves	$ 81	$ 69
Incurred but not reported reserves	36	30
Discounting	(1)	(1)
Provisions for adverse deviation	5	7
Total loss reserves	$ 121	$ 105	$ 0

The amount of liability for claims reported by policyholders as the result of the occurrence of insured events. [Refer: Types of insurance contracts [member]]

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant