Goodwill and Other Intangibles (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2015	Jun. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in the carrying value of goodwill by reporting segment
Goodwill, Beginning balance	$ 199		$ 199	$ 201	$ 185	$ 185
Goodwill, Acquired during period		$ 16		16
Goodwill, Sale of subsidiary	(2)		(2)
Goodwill, Ending balance	199		199	201
Property and Casualty [Member]
Changes in the carrying value of goodwill by reporting segment
Goodwill, Beginning balance	168		168	168	152	152
Goodwill, Acquired during period				16
Goodwill, Sale of subsidiary			0
Goodwill, Ending balance	168		168	168
Annuity [Member]
Changes in the carrying value of goodwill by reporting segment
Goodwill, Beginning balance	31		31	33	$ 33	$ 33
Goodwill, Acquired during period				0
Goodwill, Sale of subsidiary			(2)
Goodwill, Ending balance	$ 31		$ 31	$ 33