Supplemental Disclosure of Cash Flow Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash paid during the period for:
Income taxes, net	$ 28,746	$ 26,073
Interest	13,283	16,023
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	$ 91	$ 83