Fair Value Measurements (Details 1) (USD $) In Thousands	3 Months Ended
Jun. 30, 2011	Mar. 31, 2011	Jun. 30, 2010	Mar. 31, 2010
Changes in fair value of level 3 assets
Fair value at beginning of year	$ 2,401	$ 2,295	$ 4,515	$ 4,694
Settlement				(8,342)
Sales	(55)	(144)	(395)	(100)
Gains and (losses)-unrealized	140	252	323	(79)
Gains and (losses)-realized		(2)		8,342
Fair value at June 30	2,486	2,401	4,443	4,515
Fixed Income Securities [Member]
Changes in fair value of level 3 assets
Fair value at beginning of year	1,281	1,438	4,224	4,262
Sales	(55)	(144)	(395)	(100)
Gains and (losses)-unrealized	18	(11)	144	62
Gains and (losses)-realized		(2)
Fair value at June 30	1,244	1,281	3,973	4,224
Other Assets [Member]
Changes in fair value of level 3 assets
Fair value at beginning of year	1,120	857	291	432
Settlement				(8,342)
Gains and (losses)-unrealized	122	263	179	(141)
Gains and (losses)-realized				8,342
Fair value at June 30	$ 1,242	$ 1,120	$ 470	$ 291

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Realized Gain Loss Included In Earnings.

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- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Unrealized Gain Loss Included In Earnings.

+ Details

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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.

+ Details

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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

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

+ Details

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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

+ Details

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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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