Fair Value Measurements (Reconciliation Of Changes In Fair Value Of Level III Financial Assets) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2011	Sep. 30, 2011
Fair Value Measurements [Abstract]
Balance at beginning of period	$ 17,248	$ 17,482
Change in accrued interest receivable	12	(17)
Redemptions	0	(250)
Reversal of temporary loss on redeemed securities	0	45
Unrealized gains included in other comprehensive income	112	112
Balance at end of period	$ 17,372	$ 17,372

Fair value, measurement with unobservable inputs reconciliation, recurring basis, assets, redemption

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- Definition

Fair value, measurement with unobservable inputs reconciliation, recurring basis, change in accrued interest receivable

+ Details

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- Definition

Fair value, measurement with unobservable inputs reconciliation, recurring basis, reversal of temporary loss on redeemed securities

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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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

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

+ Details

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