Reconciliation of Shares Used in Basic and Diluted Net Income Per Share Computation (Parenthetical) (Detail) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2011	Jan. 01, 2011
Earnings Per Share Disclosure [Line Items]
Dilutive participating securities, excluded from EPS calculation	10	298

This element represents nonvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). Basic and dilutive earnings per share are generally disclosed for such shares using the two-class method.

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+ Details