Supplemental Disclosure of Cash Flow Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Cash paid during the period for:
Income taxes, net	$ 6,740	$ 2,541
Interest	6,208	6,143
Non-cash financing activities:
Increase in interest expense - amortization of debt discount on 8.875% Senior Note	$ 27	$ 25

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

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-Publisher FASB

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-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-03.8)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Article 5

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

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The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

+ References

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