Consolidated Statements Of Operations (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Non Variable Interest Entity [Member] | Financial Guarantee Insurance Segment [Member]
Ceded premiums earned	$ 2	$ 2	$ 5	$ 7