BUSINESS COMBINATION (Details - Identified Intangible Assets Acquired) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)
Validus Holdings, Ltd
Business Acquisition [Line Items]
Definite and indefinite lived intangibles	$ 1,010
Syndicate Capacity \| Validus Holdings, Ltd
Business Acquisition [Line Items]
Indefinite lived intangibles	193
Other \| Validus Holdings, Ltd
Business Acquisition [Line Items]
Indefinite lived intangibles	75
Value of Distribution Network Acquired
Business Acquisition [Line Items]
Definite lived intangibles	582
Value of Distribution Network Acquired \| Validus Holdings, Ltd
Business Acquisition [Line Items]
Definite lived intangibles	$ 444
Definite lived intangibles, weighted average useful life	15 years
Value of Business Acquired \| Validus Holdings, Ltd
Business Acquisition [Line Items]
Definite lived intangibles	$ 298
Definite lived intangibles, weighted average useful life	2 years

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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