Goodwill (Key Ratios To Measure Goodwill Of Bank Reporting Unit For Impairment) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2011	May 31, 2011
Bank Reporting Unit [Member]
Goodwill [Line Items]
Goodwill	$ 915,421	$ 915,421
Fair value of the bank reporting unit exceeded carrying value	13.80%	13.00%
Interim [Member]
Goodwill [Line Items]
Price to book	1.36
Price to tangible book	1.60
Annual [Member]
Goodwill [Line Items]
Price to book		1.36
Price to tangible book		1.60

Carrying amount of goodwill allocated to the bank reporting unit.

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- Definition

Market multiple used, in part, to determine the fair value of the bank reporting unit.

+ Details

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- Definition

Market multiple used, in part, to determine the fair value of the bank reporting unit.

+ Details

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- Definition

Percentage By Which Fair Value Of Bank Reporting Unit Exceeded Its Carrying Value

+ Details

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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.

+ Details

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