|
Segment Reporting Disclosures (Reconciliation Of Segment Assets To The Company's Consolidated Balance Sheets (Details) (USD $)
In Thousands, unless otherwise specified |
Sep. 30, 2012
|
Dec. 31, 2011
|
|---|---|---|
| Segment Reporting, Asset Reconciling Item [Line Items] | ||
| Assets | $ 12,383,417 | $ 11,532,103 |
|
Non-Insurance Operations [Member]
|
||
| Segment Reporting, Asset Reconciling Item [Line Items] | ||
| Assets | 853,694 | 630,281 |
|
Segment Assets [Member]
|
||
| Segment Reporting, Asset Reconciling Item [Line Items] | ||
| Assets | 11,529,723 | 10,901,822 |
|
Segment Assets [Member] | Investing [Member]
|
||
| Segment Reporting, Asset Reconciling Item [Line Items] | ||
| Assets | 9,137,910 | 8,692,391 |
|
Segment Assets [Member] | Underwriting [Member]
|
||
| Segment Reporting, Asset Reconciling Item [Line Items] | ||
| Assets | $ 2,391,813 | $ 2,209,431 |