v2.3.0.15

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Level 3 Inputs) (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Balance at beginning of the period	$ 475,379	$ 329,816	$ 400,386	$ 410,939
Total net unrealized (losses) gains, Included in net investment income	(25,612)	156	3,759	3,323
Total net unrealized gains (losses), Included in other income (loss)	(46,116)	(6,496)	(4,517)	(6,482)
Total net realized gains (losses), Included in other income (loss)	48,393	18,237	61,215	31,349
Total net foreign exchange losses	(2,566)	2,338	(786)	(1,629)
Purchases	45,684	39,874	84,983	63,849
Sales	(19,860)		(30,884)
Issuances		(12,181)		(39,414)
Settlements	(66,174)	(25,431)	(105,028)	(115,622)
Balance at end of the period	409,128	346,313	409,128	346,313
Fixed Maturity Investments [Member]
Balance at beginning of the period	21,264		21,785
Total net unrealized (losses) gains, Included in net investment income	(350)		(871)
Balance at end of the period	20,914		20,914
Other Investments Level 3 [Member]
Balance at beginning of the period	381,123	314,663	362,102	393,913
Total net unrealized (losses) gains, Included in net investment income	(25,262)	156	4,630	3,323
Total net foreign exchange losses	(2,511)	2,354	(589)	(912)
Purchases	19,460	31,727	48,144	51,401
Settlements	(9,173)	(15,035)	(50,650)	(113,860)
Balance at end of the period	363,637	333,865	363,637	333,865
Other Assets and Liabilities [Member]
Balance at beginning of the period	72,992	15,153	16,499	17,026
Total net unrealized gains (losses), Included in other income (loss)	(46,116)	(6,496)	(4,517)	(6,482)
Total net realized gains (losses), Included in other income (loss)	48,393	18,237	61,215	31,349
Total net foreign exchange losses	(55)	(16)	(197)	(717)
Purchases	26,224	8,147	36,839	12,448
Sales	(19,860)		(30,884)
Issuances		(12,181)		(39,414)
Settlements	(57,001)	(10,396)	(54,378)	(1,762)
Balance at end of the period	$ 24,577	$ 12,448	$ 24,577	$ 12,448

X

- Definition

This item represents the amount of the total foreign exchange gains or losses for the period which are included in the statement of income in net foreign exchange gains or losses. Such foreign exchange gains or losses relate to those assets or liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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- Definition

This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets) in investment income. Such unrealized (holding) gains or losses relate to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph d

-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.



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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph d

-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 2: http://www.xbrl.org/2003/role/presentationRef

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- Definition

This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets) in other income; the fair value of which assets was or is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1)

-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.



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- Definition

Issues that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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- Definition

Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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- Definition

Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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- Definition

Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

-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.



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