Securities (Details Textual) (USD $)	3 Months Ended
Dec. 31, 2011 Y MortgageObligation
Securities (Textual) [Abstract]
Gross unrealized losses attributable to collateralized mortgage obligations	$ 1,000,000
Number of fixed rate collateralized mortgage obligations	2
Weighted-average maturity collateralized mortgage, in years	0.2
Impairment recognized in earnings	0
Pledged available for sale and Held-To-Maturity securities	$ 11,500,000,000

Gross unrealized losses attributable to collateralized mortgage obligations.

No definition available.

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Period Type:	instant

- Definition

Number of fixed-rate collateralized mortgage obligations.

+ References

No definition available.

+ Details

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- Details

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- Definition

Weighted-average maturity collateralized mortgage, in years.

+ References

No definition available.

+ Details

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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor shall reclassify that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 15

-Subparagraph a

+ Details

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- Definition

This element represents the amount of loss recognized for other than temporary impairments of investments in debt and equity securities.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 16

+ Details

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