Income Taxes Changes in unrecognized tax benefit (Details) (USD $) In Thousands	12 Months Ended
Sep. 30, 2011
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Unrecognized Tax Benefits, Beginning Balance	$ 19,900
Increase based on positions related to prior years	935
Increases based on positions related to current year	11,334
Decreases relating to settlements with taxing authorities	0
Decreases relating to lapses of applicable statues of limitations	(33)
Unrecognized Tax Benefits, Ending Balance	$ 32,136

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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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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