Fair Value Measurements (Summarize Changes in Level 3 Assets) (Details) (USD $) In Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Beginning Balance	$ 182,255	$ 172,685
Earnings	28,153	22,332
Other Comprehensive Income	(30,027)	33,191
Purchases	8,464	42,361
(Sales)	(76,239)	(45,301)
Maturities	(16,936)	(17,113)
Transfer out	0	(25,900)
Ending Balance	95,670	182,255
Mortgage-Backed Securities [Member] \| Fixed Maturities Securities [Member]
Beginning Balance		25,900
Earnings		0
Other Comprehensive Income		0
Purchases		0
(Sales)		0
Maturities		0
Transfer out		(25,900)
Ending Balance		0
Corporate [Member] \| Fixed Maturities Securities [Member]
Beginning Balance	88,063	90,160
Earnings	20	(850)
Other Comprehensive Income	(386)	1,558
Purchases	8,195	19,632
(Sales)	(3,952)	(5,324)
Maturities	(16,936)	(17,113)
Transfer out	0	0
Ending Balance	75,004	88,063
Common Stocks [Member] \| Equity Securities Available For Sale [Member]
Beginning Balance	1,559	1,559
Earnings	0	0
Other Comprehensive Income	0	0
Purchases	0	0
(Sales)	0	0
Maturities	0	0
Transfer out	0	0
Ending Balance	1,559	1,559
Preferred Stocks [Member] \| Equity Securities Available For Sale [Member]
Beginning Balance	89,446	54,713
Earnings	27,338	23,535
Other Comprehensive Income	(29,641)	31,633
Purchases	0	19,542
(Sales)	(69,053)	(39,977)
Maturities	0	0
Transfer out	0	0
Ending Balance	18,090	89,446
Arbitrage Trading Account [Member]
Beginning Balance	3,187	353
Earnings	795	(353)
Other Comprehensive Income	0	0
Purchases	269	3,187
(Sales)	(3,234)	0
Maturities	0	0
Transfer out	0	0
Ending Balance	1,017	3,187
Equity Securities Available For Sale [Member]
Beginning Balance	91,005	56,272
Earnings	27,338	23,535
Other Comprehensive Income	(29,641)	31,633
Purchases	0	19,542
(Sales)	(69,053)	(39,977)
Maturities	0	0
Transfer out	0	0
Ending Balance	19,649	91,005
Fixed Maturities Securities [Member]
Beginning Balance	88,063	116,060
Earnings	20	(850)
Other Comprehensive Income	(386)	1,558
Purchases	8,195	19,632
(Sales)	(3,952)	(5,324)
Maturities	(16,936)	(17,113)
Transfer out	0	(25,900)
Ending Balance	$ 75,004	$ 88,063

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 earnings or resulted in a change in net asset value.

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

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

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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

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 [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.

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)(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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