XML 17 R46.htm IDEA: XBRL DOCUMENT v2.4.0.6
Investments (Aggregated Income Statement Summarized Financial Information for Partnerhips in our Alternative Investment Portfolio) (Details) (USD $)
 3 Months Ended 9 Months Ended
Sep. 30, 2012
Jun. 30, 2012
Sep. 30, 2011
Jun. 30, 2011
Sep. 30, 2012
Jun. 30, 2012
Sep. 30, 2011
Jun. 30, 2011
Schedule of Equity Method Investments [Line Items]                
Net investment income   $ 80,000,000   $ 136,800,000   $ 170,100,000   $ 423,600,000
Realized gains (losses)   19,600,000   710,600,000   1,004,900,000   873,600,000
Net change in unrealized (depreciation) appreciation   (117,100,000)   (194,700,000)   (551,100,000)   1,877,800,000
Net income   (17,500,000)   652,700,000   623,900,000   3,175,000,000
Net investment income earned 30,650,000   35,786,000   97,284,000   118,604,000  
Alternative Investments [Member]
                
Schedule of Equity Method Investments [Line Items]                
Net investment income earned   $ 500,000   $ 4,500,000   $ 5,500,000   $ 24,000,000