GOODWILL AND OTHER INTANGIBLE ASSETS (Details - Goodwill) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($) item	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
GOODWILL AND OTHER INTANGIBLE ASSETS
Number of steps involved in process of impairment test \| item	2
Goodwill
Goodwill - gross	$ 5,071	$ 5,005	$ 5,090
Accumulated impairments	(3,477)	(3,477)	(3,477)
Net goodwill	1,594	1,528	1,613
Increase (decrease) due to:
Acquisition	2,544	4	0
Other	(56)	87	(73)
Dispositions	0	(25)	(12)
Goodwill - gross	7,559	5,071	5,005
Accumulated impairments	(3,477)	(3,477)	(3,477)
Net goodwill	4,082	1,594	1,528
Validus Holdings, Ltd
Increase (decrease) due to:
Acquisition	2,000
Glatfelter
Increase (decrease) due to:
Acquisition	492
Ellipse
Increase (decrease) due to:
Acquisition	46
North America
Goodwill
Goodwill - gross	1,868	1,878	1,884
Accumulated impairments	(1,264)	(1,264)	(1,264)
Net goodwill	604	614	620
Increase (decrease) due to:
Acquisition	2,332	0	0
Other	(12)	0	0
Dispositions	0	(10)	(6)
Goodwill - gross	4,188	1,868	1,878
Accumulated impairments	(1,264)	(1,264)	(1,264)
Net goodwill	2,924	604	614
International
Goodwill
Goodwill - gross	2,874	2,807	2,883
Accumulated impairments	(2,136)	(2,136)	(2,136)
Net goodwill	738	671	747
Increase (decrease) due to:
Acquisition	157	0	0
Other	(48)	74	(70)
Dispositions	0	(7)	(6)
Goodwill - gross	2,983	2,874	2,807
Accumulated impairments	(2,136)	(2,136)	(2,136)
Net goodwill	847	738	671
Life Insurance
Goodwill
Goodwill - gross	84	77	77
Accumulated impairments	0	0	0
Net goodwill	84	77	77
Increase (decrease) due to:
Acquisition	46	0	0
Other	(5)	13	0
Dispositions	0	(6)	0
Goodwill - gross	125	84	77
Accumulated impairments	0	0	0
Net goodwill	125	84	77
Other Operations
Goodwill
Goodwill - gross	31	27	27
Accumulated impairments	0	0	0
Net goodwill	31	27	27
Increase (decrease) due to:
Acquisition	9	4	0
Other	9	0	0
Dispositions	0	0	0
Goodwill - gross	49	31	27
Accumulated impairments	0	0	0
Net goodwill	49	31	27
Legacy Portfolio
Goodwill
Goodwill - gross	214	216	219
Accumulated impairments	(77)	(77)	(77)
Net goodwill	137	139	142
Increase (decrease) due to:
Acquisition	0	0	0
Other	0	0	(3)
Dispositions	0	(2)	0
Goodwill - gross	214	214	216
Accumulated impairments	(77)	(77)	(77)
Net goodwill	$ 137	$ 137	$ 139

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