Investments (Details 18)	Jun. 30, 2011	Dec. 31, 2010
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	100.00%	100.00%
Percentage of gross unrealized loss and OTTI loss by industry	100.00%	100.00%
ABS [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	10.00%	10.00%
Percentage of gross unrealized loss and OTTI loss by industry	10.00%	10.00%
U.S. corporate securities [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	21.00%	23.00%
RMBS [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	21.00%	20.00%
CMBS [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	3.00%	4.00%
U.S. Treasury, agency and government guaranteed securities [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	11.00%	8.00%
Percentage of gross unrealized loss and OTTI loss by industry	11.00%	8.00%
State and political subdivision securities [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	6.00%	8.00%
Percentage of gross unrealized loss and OTTI loss by industry	6.00%	8.00%
Foreign government debt securities [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	10.00%	9.00%
Percentage of gross unrealized loss and OTTI loss by industry	10.00%	9.00%
Communications [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by industry	2.00%	2.00%
Consumer [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by industry	4.00%	4.00%
Utility [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by industry	10.00%	5.00%
Industrial [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by industry	1.00%	2.00%
Mortgage-backed [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by industry	24.00%	24.00%
Other sectors [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	2.00%	4.00%
Foreign corporate securities [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by sector	16.00%	14.00%
Other industries [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by industry	7.00%	7.00%
Finance Domestic Corporate Debt Securities [Member]
Concentration of Gross Unrealized Loss and OTTI Loss for Fixed Maturity and Equity Securities Available-for-Sale
Percentage of gross unrealized loss and OTTI loss by industry	15.00%	21.00%