Consolidated Statements Of Operations (Parenthetical) (Non Variable Interest Entities [Member], USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Non Variable Interest Entities [Member]
Premiums earned, ceded premiums	$ 6	$ 3	$ 9	$ 6