Represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in net investment income.

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- Definition

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

+ 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(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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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- Definition

This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

+ References

+ Details

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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

Transfers into assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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- Definition

This element represents [net] transfers in to and out of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

+ 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(3)
-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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-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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- Definition

Transfers out of assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 16B
-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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-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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Fair Value Measurements (Details 2) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended				3 Months Ended	6 Months Ended	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended				3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended
Fair Value Measurements (Details 2) (USD $)	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2010 Foreign governments Investments, available for sale	Jun. 30, 2010 Foreign governments Investments, available for sale	Jun. 30, 2011 Foreign governments Investments, available for sale	Mar. 31, 2011 Foreign governments Investments, available for sale	Dec. 31, 2010 Foreign governments Investments, available for sale	Jun. 30, 2011 U.S. corporate Investments, available for sale	Jun. 30, 2011 U.S. corporate Investments, available for sale	Jun. 30, 2011 Asset-backed: RMBS Investments, available for sale	Jun. 30, 2010 Asset-backed: RMBS Investments, available for sale	Jun. 30, 2011 Asset-backed: RMBS Investments, available for sale	Jun. 30, 2010 Asset-backed: RMBS Investments, available for sale	Jun. 30, 2011 Asset-backed: CMBS Investments, available for sale	Jun. 30, 2010 Asset-backed: CMBS Investments, available for sale	Jun. 30, 2011 Asset-backed: CMBS Investments, available for sale	Jun. 30, 2010 Asset-backed: CMBS Investments, available for sale	Jun. 30, 2011 Other asset-backed Investments, available for sale	Jun. 30, 2010 Other asset-backed Investments, available for sale	Jun. 30, 2011 Other asset-backed Investments, available for sale	Jun. 30, 2010 Other asset-backed Investments, available for sale	Jun. 30, 2011 Equities Investments, available for sale	Jun. 30, 2011 Equities Investments, available for sale	Jun. 30, 2010 Equities Investments, available for sale	Mar. 31, 2010 Equities Investments, available for sale	Dec. 31, 2009 Equities Investments, available for sale	Jun. 30, 2011 Other invested assets	Jun. 30, 2010 Other invested assets	Jun. 30, 2011 Other invested assets	Jun. 30, 2010 Other invested assets	Jun. 30, 2011 Other assets.	Jun. 30, 2010 Other assets.	Jun. 30, 2011 Other assets.	Jun. 30, 2010 Other assets.
Changes in Level 3 assets measured at fair value on a recurring basis
Balance at beginning of period	$ 186,600,000	$ 147,000,000	$ 230,000,000	$ 150,000,000		$ 1,400,000	$ 800,000	$ 800,000	$ 800,000		$ 6,500,000	$ 26,800,000	$ 19,200,000	$ 26,700,000	$ 18,600,000	$ 78,100,000	$ 33,900,000	$ 91,200,000	$ 32,700,000	$ 12,400,000	$ 16,300,000	$ 13,400,000	$ 17,600,000	$ 5,000,000	$ 5,000,000	$ 7,500,000	$ 7,500,000	$ 7,500,000	$ 63,500,000	$ 67,700,000	$ 86,400,000	$ 72,200,000		$ 2,400,000
Net realized/unrealized gains (losses) included in net investment income	(100,000)	1,400,000	(10,400,000)	(2,300,000)								200,000	500,000	700,000	100,000	(100,000)	(100,000)	(400,000)	(200,000)		100,000		100,000						(200,000)	900,000	(10,700,000)	(2,300,000)
Net realized/unrealized gains (losses) included in realized net capital gains (losses)				(6,100,000)											(6,100,000)
Net realized/unrealized gains (losses) included in AOCI	2,100,000	2,700,000	4,900,000	13,900,000		200,000						(300,000)	(100,000)	600,000	8,700,000	2,200,000	3,100,000	3,700,000	4,800,000	200,000	300,000	500,000	600,000							(600,000)	100,000	(400,000)
Purchases	4,700,000		4,700,000																					2,000,000	2,000,000								2,700,000		2,700,000
Sales			(12,500,000)																												(12,500,000)
Settlements	(2,500,000)		(5,700,000)									(1,000,000)		(2,300,000)		(900,000)		(1,500,000)		(600,000)		(1,900,000)
Purchases, Sales, Issuances and Settlements, net		111,400,000		107,000,000		(1,600,000)							(1,600,000)		(3,300,000)		92,300,000		91,900,000		20,600,000		19,000,000									(1,500,000)		100,000		2,500,000
Transfers in (out) of Level 3		2,500,000		2,500,000	700,000	700,000											1,800,000		1,800,000
Transfers into Level 3	19,000,000		19,000,000							6,300,000	6,300,000	12,700,000		12,700,000
Transfers out of Level 3	(5,600,000)		(25,800,000)								(6,500,000)							(13,700,000)		(5,600,000)		(5,600,000)
Balance at end of period	204,200,000	265,000,000	204,200,000	265,000,000	700,000	700,000	800,000	800,000	800,000	6,300,000	6,300,000	38,400,000	18,000,000	38,400,000	18,000,000	79,300,000	131,000,000	79,300,000	131,000,000	6,400,000	37,300,000	6,400,000	37,300,000	7,000,000	7,000,000	7,500,000	7,500,000	7,500,000	63,300,000	68,000,000	63,300,000	68,000,000	2,700,000	2,500,000	2,700,000	2,500,000
OTTI recorded in realized net capital losses	$ 1,639,000		$ 3,139,000	$ 6,332,000											$ 6,100,000