Long - Term Debt and Bank Facility Borrowings (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended			1 Months Ended	12 Months Ended	9 Months Ended		1 Months Ended		12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Jul. 31, 2011	Nov. 30, 2011 First Amendment [Member]	Sep. 30, 2012 First Amendment [Member]	Dec. 31, 2012 Second Amendment [Member]	Sep. 30, 2012 Second Amendment [Member]	Dec. 01, 2012 8.875% Senior Notes [Member]	Jun. 01, 2012 8.875% Senior Notes [Member]	Sep. 30, 2012 8.875% Senior Notes [Member]	Sep. 30, 2012 Senior Notes [Member]
Long-Term Debt and Bank Facility Borrowings (Textual) [Abstract]
Maturity of public notes due										2017-12
Interest accrued by public notes for each year								8.875%	8.875%
Discount on notes										$ 0.6
Maximum debt allowed for acquisitions										100
Maximum borrowing capacity (non-heating season) under revolving credit facility					250
Increase in credit facility				50
Maximum borrowing capacity (heating season December to April) under revolving credit facility					350
Facility size that can be increased without consulting bank group					100
Description of Variable Rate					The interest rate is LIBOR plus (i) 1.75% (if Availability, as defined in the revolving credit facility agreement is greater than or equal to $150 million), or (ii) 2.00% (if Availability is greater than $75 million but less than $150 million), or (iii) 2.25% (if Availability is less than or equal to $75 million). The commitment fee on the unused portion of the facility is 0.375% per annum.
Debt instrument basis of spread percentage one					1.75%
Debt instrument basis of spread percentage two					2.00%
Debt instrument basis of spread percentage three					2.25%
Minimum revolving credit facility agreement one					150
Maximum revolving credit facility agreement two					150
Minimum revolving credit facility agreement two					75
Minimum revolving credit facility agreement three					75
Commitment fee on the unused portion of the facility					0.375%
Availability to maintain					43.8
Availability percentage to maximum facility size					12.50%
Minimum fixed charge coverage ratio					1.1
Availability required to make acquisitions on a historical pro forma and forward-looking basis					40
Availability required to pay distributions or repurchase common units on a historical pro forma and forward-looking basis					61.3
Percentage of the maximum facility size on a historical pro forma and forward-looking basis					17.50%
Minimum fixed charge ratio for distributions to unit holders or repurchase common units					1.15
Availability required to pay distributions for the period April 1, 2012 to December 31, 2012						50.0
Maximum payment of distributions per common unit for the period April 1, 2012 to December 31, 2012						0.2325
Borrowing base for fixed assets and customer lists before amendment							50.0
Borrowing base for fixed assets and customer lists							60.0
Amount of additional subordinated debt							25.0
Senior notes issuance date											Nov. 30, 2010
Maximum investment in an unrestricted subsidiary before amendment							10.0
Maximum investment in unrestricted subsidiary							20.0
Long - Term Debt and Bank Facility Borrowings (Additional Textual) [Abstract]
Restricted payments without passing certain financial tests	22.0
Revolving credit facility expiry	2016-06
Amount outstanding under the revolving credit facility	0	0
Letters of credit issued	42.8	46.7
Availability	179.2	162.4
Available sale of offerings of common units, partnership securities and debt securities under shelf registration	0		250
Amount outstanding of Available sale of offerings of common units, partnership securities and debt securities under shelf registration	0
Aggregate amount of restricted net asset	$ 378	$ 390