Noncovered Loans Noncovered Loans (Analysis of Troubled Debt Restructurings) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012 contract	Mar. 31, 2011 Noncovered Loans [Member] Modifications	Mar. 31, 2011 Noncovered Loans [Member] Residential Construction [Member] Modifications
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts		1	1
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 36	$ 36
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 36	$ 36
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0

Financing Receivable, Modifications, Subsequent Default, Number of Contracts

No definition available.

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- Details

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- Definition

The number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 32

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953670-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953676-111524

+ Details

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings after the financing receivable has been modified.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings before the financing receivable has been modified.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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