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Indebtedness (Narrative) (Details) (USD $) | 12 Months Ended |  |  |  |  |  |  | 12 Months Ended |  |  |  |  |
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Dec. 31, 2006 | Dec. 31, 2011 | Sep. 30, 2011 | Dec. 31, 2010 | Sep. 25, 2006 | Dec. 31, 2011 Seven Point Twenty Five Percent Senior Notes [Member] | Nov. 15, 2004 Seven Point Twenty Five Percent Senior Notes [Member] | Dec. 31, 2005 Six Point Seventy Percent Senior Notes [Member] | Dec. 31, 2011 Six Point Seventy Percent Senior Notes [Member] | Nov. 03, 2005 Six Point Seventy Percent Senior Notes [Member] | Dec. 31, 2011 Two Point Ninety Percent Borrowing From Federal Home Loan Bank [Member] | Dec. 31, 2009 Two Point Ninety Percent Borrowing From Federal Home Loan Bank [Member] | Dec. 31, 2011 One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member]
Aggregate principal amount of notes |  |  |  |  | $ 100,000,000 |  | $ 50,000,000 |  |  | $ 100,000,000 |  |  |
Discount for notes issued |  |  |  |  |  |  | 100,000 |  |  | 700,000 |  |  |
Effective yield |  |  |  |  |  |  | 7.27% |  |  | 6.754% |  |  |
Bond proceeds to Insurance Subsidiaries as capital |  |  |  |  |  |  | 25,000,000 |  |  |  |  |  |
Acceleration of principal |  | 10,000,000 |  |  |  | 10,000,000 |  |  | 10,000,000 |  |  |  |
Net proceeds from the issuance | 96,800,000 |  |  |  |  |  |  | 50,000,000 |  |  |  |  |
Deferred interest payments |  |  |  |  | 10 |  |  |  |  |  |  |  |
Aggregate investment in FHLBI |  | 2,900,000 |  | 800,000 |  |  |  |  |  |  |  |  |
Borrowing threshold of FHLBI |  | 20 |  |  |  |  |  |  |  |  |  |  |
FLHBI Borrowing |  | 58,000,000 | 13,000,000 |  |  |  |  |  |  |  |  | 13,000,000 | 45,000,000
Unpaid principal amount interest rate |  |  |  |  |  |  |  |  |  |  | 2.90% |  | 1.25%
Line of credit borrowing capacity |  | 30,000,000 |  |  |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity |  | $ 50,000,000 |  |  |  |  |  |  |  |  |  |  |
Maximum FHLBI borrowing percentage permitted by line of credit |  | 10.00% |  |  |  |  |  |  |  |  |  |  |

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