Partnership's Debt (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended		1 Months Ended
	Sep. 30, 2013	Sep. 30, 2013 8.875% Senior Notes	Nov. 22, 2011 First Amendment
Debt Instrument [Line Items]
Senior notes issuance date		Nov. 01, 2010
Interest accrued by public notes for each year		8.875%
Discount on notes		$ 0.5
Maximum debt allowed for acquisitions		100
Restricted payments without passing certain financial tests		22
Maturity of public notes due		Dec. 01, 2017
Interest payment frequency		Semi-annual interest payments on June 1 and December 1 of each year.
Revolving credit facility expiry	Jun. 03, 2016
Increase in credit facility			50
Maximum borrowing capacity under revolving credit facility	350		250
Maximum borrowing capacity (heating season December to April) under revolving credit facility			350
Facility size that can be increased without consulting bank group	100
Maximum issuable letter of credit	$ 100