Goodwill (Key Ratios Used To Measure Goodwill Of Property And Casualty Insurance Reporting Unit For Impairment) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2011	May 31, 2011	May 31, 2010
Property And Casualty Insurance Reporting Unit [Member]
Goodwill [Line Items]
Goodwill		$ 17,177	$ 17,177
Number of key ratios used	2
Fair value of the property and casualty insurance reporting unit exceeding carrying value		48.40%	33.90%
Annual [Member]
Goodwill [Line Items]
Average price to book		1.23	1.06
Median price to earnings		13.80	8.50

Average Price To Book Value Ratio Used To Determine Fair Value Of Property And Casualty Insurance Reporting Unit

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- Definition

Goodwill Allocated To Property And Casualty Insurance Reporting Unit

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- Definition

Median Price To Earnings Ratio Used To Determine Fair Value Of Property And Casualty Insurance Reporting Unit

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- Definition

Number Of Key Ratios Used To Determine Fair Value Of Property And Casualty Insurance Reporting Unit

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- Definition

Percentage By Which Property And Casualty Insurance Reporting Unit Exceeded Its Carrying Value

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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