Supplemental Disclosure of Cash Flow Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Non-cash investing activities:
Acquisition of NYC heating oil customer list	$ 886
Non-cash financing activities:
Increase in interest expense-amortization of debt discount on 8.875% Senior Notes	30	27
Income taxes, net	11,116us-gaap_IncomeTaxesPaidNet	6,740us-gaap_IncomeTaxesPaidNet
Interest	$ 6,233us-gaap_InterestPaidNet	$ 6,208us-gaap_InterestPaidNet

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Noncash Increase in Intangible Assets from Business Combination

+ References

No definition available.

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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

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-Subparagraph (SX 210.5-03.8)

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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.

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

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