v2.4.0.6

Investments (Schedule Of Fair Value Of Fixed Maturity Investments Trading) (Details) (USD $) In Thousands, unless otherwise specified | Jun. 30, 2012 | Dec. 31, 2011
--- | --- | ---
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | $ 4,948,955 | $ 4,291,465
U.S. treasuries [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | 1,126,759 | 885,152
Agencies [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | 436,691 | 158,561
Non-U.S. government (Sovereign Debt) [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | 172,008 | 216,916
FDIC guaranteed corporate [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | 29,386 | 423,630
Non-U.S. government-backed corporate [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | 393,875 | 640,757
Corporate [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | 1,652,007 | 1,187,437
Agency mortgage-backed [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | 580,971 | 428,042
Non-agency mortgage-backed [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | 135,268 | 82,096
Commercial mortgage-backed [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | 414,524 | 255,885
Asset-backed [Member] |  |
Investment [Line Items] |  |
Fixed maturity investments trading, fair value | $ 7,466 | $ 12,989

X
- Details
Name: | invest_InvestmentLineItems
Namespace Prefix: | invest_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Debt securities that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for debt securities formerly categorized as available-for-sale or held-to-maturity which the entity held as of the date it opted to account for such securities at fair value. An enterprise may also categorize such a security as trading without the intent to sell it in the near term assuming the decision to categorize the security as trading occurred at acquisition. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 159 -Paragraph 29 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),1) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Implementation Guide (Q and A) -Number FAS115 -Paragraph 35 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
Name: | us-gaap_TradingSecuritiesDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant