Invested Assets (Details Textual) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012 Investment	Dec. 31, 2011
Invested Assets (Textual) [Abstract]
Fixed maturities other-than-temporary impairment losses in gross unrealized depreciation		$ 3
Approximate number of individual fixed maturity and equity securities in unrealized loss position	300
Approximate number of individual fixed maturities in unrealized loss position	270
Cumulative credit losses recognized in net income	$ 20	$ 20