Estimated Future Intangible Asset Amortization Expense (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2012
Estimated future intangible asset amortization expense
Remainder of fiscal 2012	$ 2,749
2013	4,126
2014	2,407
2015	2,407
2016	2,407
Thereafter	2,024
Finite-Lived Intangible Assets, Future Amortization Expense, Total	$ 16,120

Future Amortization Expense, Thereafter

No definition available.

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- Definition

The aggregate estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

+ Details

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- Definition

The amount of amortization expense expected to be recognized during the remainder of the current fiscal year.

+ References

No definition available.

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

+ References

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

+ References

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

+ References

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

+ References

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