Other Intangible Assets (Summary of Other Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Schedule of Other Intangible Assets [Abstract]
Finite-lived intangible assets:	$ 18	$ 16
Indefinite-lived intangible assets:	62	61
Total other intangible assets	80	77
Accumulated Amortization	11	9
Syndicate capacity
Schedule of Other Intangible Assets [Abstract]
Indefinite-lived intangible assets:	46	45
Agency force
Schedule of Other Intangible Assets [Abstract]
Indefinite-lived intangible assets:	$ 16	16
Trade name
Schedule of Other Intangible Assets [Abstract]
Economic Useful Life	8 years
Finite-lived intangible assets:	$ 7	6
Accumulated Amortization	$ 6	5
Distribution channel
Schedule of Other Intangible Assets [Abstract]
Economic Useful Life	15 years
Finite-lived intangible assets:	$ 11	10
Accumulated Amortization	$ 5	$ 4