XML 63 R49.htm IDEA: XBRL DOCUMENT v3.3.0.814
Fair Value Measurements (Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($)
Sep. 30, 2015
Dec. 31, 2014
Sep. 30, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Transfers of Assets, Levels 1 to Level 2 $ 0   $ 0
Transfer of Assets, Level 2 to Level 1 0   0
Transfer of Liabilities, Level 1 to Level 2 0   0
Transfers of Liabilities, Levels 2 to Level 1 0   0
Recurring [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Cash and cash equivalents 972,900,000 $ 869,100,000  
Investments at fair value 2,241,400,000 1,795,600,000  
Embedded contractual derivative asset 5,800,000 10,000,000  
Total assets at fair value 3,220,100,000 2,674,700,000  
Embedded contractual derivative liability 10,100,000 2,600,000  
Total liabilities at fair value 10,100,000 2,600,000  
Recurring [Member] | Residential Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 218,100,000 210,900,000  
Recurring [Member] | Commercial Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 206,400,000 146,200,000  
Recurring [Member] | Other Asset-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 133,400,000 81,400,000  
Recurring [Member] | U.S. Treasury Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 28,100,000 36,500,000  
Recurring [Member] | U.S. Agency Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Obligations of States and Other Political Subdivisions [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 940,100,000 732,200,000  
Recurring [Member] | Corporate Debt Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 715,300,000 588,400,000  
Recurring [Member] | Level 1 [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Cash and cash equivalents 972,900,000 869,100,000  
Investments at fair value 28,100,000 36,500,000  
Embedded contractual derivative asset 0 0  
Total assets at fair value 1,001,000,000 905,600,000  
Recurring [Member] | Level 1 [Member] | Residential Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 1 [Member] | Commercial Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 1 [Member] | Other Asset-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 1 [Member] | U.S. Treasury Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 28,100,000 36,500,000  
Recurring [Member] | Level 1 [Member] | U.S. Agency Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 1 [Member] | Obligations of States and Other Political Subdivisions [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 1 [Member] | Corporate Debt Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 2 [Member] | Current Assets [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Cash and cash equivalents 0 0  
Investments at fair value 2,193,200,000 1,754,500,000  
Embedded contractual derivative asset 0 0  
Total assets at fair value 2,193,200,000 1,754,500,000  
Recurring [Member] | Level 2 [Member] | Current Assets [Member] | Residential Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 218,100,000 210,900,000  
Recurring [Member] | Level 2 [Member] | Current Assets [Member] | Commercial Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 206,000,000 145,600,000  
Recurring [Member] | Level 2 [Member] | Current Assets [Member] | Other Asset-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 133,400,000 81,400,000  
Recurring [Member] | Level 2 [Member] | Current Assets [Member] | U.S. Treasury Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 2 [Member] | Current Assets [Member] | U.S. Agency Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 2 [Member] | Current Assets [Member] | Obligations of States and Other Political Subdivisions [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 938,600,000 732,200,000  
Recurring [Member] | Level 2 [Member] | Current Assets [Member] | Corporate Debt Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 697,100,000 584,400,000  
Recurring [Member] | Level 2 [Member] | Noncurrent Assets [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Cash and cash equivalents 0 0  
Investments at fair value 20,100,000 4,600,000  
Embedded contractual derivative asset 0 0  
Total assets at fair value 20,100,000 4,600,000  
Recurring [Member] | Level 2 [Member] | Noncurrent Assets [Member] | Residential Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 2 [Member] | Noncurrent Assets [Member] | Commercial Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 400,000 600,000  
Recurring [Member] | Level 2 [Member] | Noncurrent Assets [Member] | Other Asset-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 2 [Member] | Noncurrent Assets [Member] | U.S. Treasury Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 2 [Member] | Noncurrent Assets [Member] | U.S. Agency Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 2 [Member] | Noncurrent Assets [Member] | Obligations of States and Other Political Subdivisions [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 1,500,000 0  
Recurring [Member] | Level 2 [Member] | Noncurrent Assets [Member] | Corporate Debt Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 18,200,000 4,000,000  
Recurring [Member] | Level 3 [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Cash and cash equivalents 0 0  
Investments at fair value 0 0  
Embedded contractual derivative asset 5,800,000 10,000,000  
Total assets at fair value 5,800,000 10,000,000  
Embedded contractual derivative liability 10,100,000 2,600,000  
Total liabilities at fair value 10,100,000 2,600,000 $ 0
Recurring [Member] | Level 3 [Member] | Residential Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 3 [Member] | Commercial Mortgage-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 3 [Member] | Other Asset-Backed Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 3 [Member] | U.S. Treasury Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 3 [Member] | U.S. Agency Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 3 [Member] | Obligations of States and Other Political Subdivisions [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value 0 0  
Recurring [Member] | Level 3 [Member] | Corporate Debt Securities [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Investments at fair value $ 0 $ 0