Servicing Assets and Residual Interests Economic Assumptions (Detail)	Jun. 30, 2011 Year	Jun. 30, 2010 Year
Servicing Assets at Amortized Value [Line Items]
Weighted- Average Default Rate
Fixed Rate Residential Mortgage
Servicing Assets at Amortized Value [Line Items]
Weighted- Average Life (in years)	6.6	6.1
Prepayment Speed (annual)	11.00%	12.40%
Discount Rate (annual)	10.50%	10.00%
Weighted- Average Default Rate
Adjustable Rate Residential Mortgage
Servicing Assets at Amortized Value [Line Items]
Weighted- Average Life (in years)	3.7	4.0
Prepayment Speed (annual)	22.40%	20.70%
Discount Rate (annual)	11.50%	11.20%
Weighted- Average Default Rate

- Definition

Fair Value Assumptions, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities, Discount Rate

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- Definition

Fair Value Assumptions, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities, Expected Credit Losses

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- Definition

Fair Value Assumptions, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities, Prepayment Speed

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- Definition

Fair Value Assumptions, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities, Weighted Average Life

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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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