Partnership's Debt (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Sep. 30, 2013
Debt Instrument [Line Items]
8.875% Senior Notes, Carrying Amount	$ 124,515	[1]	$ 124,460	[1]
Revolving Credit Facility Borrowings, Carrying Amount	165,741	[2]
Total debt, Carrying Amount	290,256		124,460
Total long-term portion of debt, Carrying Amount	124,515		124,460
8.875% Senior Notes, Fair Value	132,813	[1],[3]	130,000	[1],[3]
Revolving Credit Facility Borrowings, Fair Value	165,741	[2],[3]
Total debt, Fair Value	298,554	[3]	130,000	[3]
Total long-term portion of debt, Fair Value	$ 132,813	[1],[3]	$ 130,000	[1],[3]

[1] The 8.875% Senior Notes were originally issued in November 2010 in a private placement offering pursuant to Rule 144A and Regulation S under the Securities Act of 1933, and in February 2011, were exchanged for substantially identical public notes registered with the Securities and Exchange Commission. These public notes mature in December 2017 and accrue interest at an annual rate of 8.875% requiring semi-annual interest payments on June 1 and December 1 of each year. The discount on these notes was $0.5 million at March 31, 2014. Under the terms of the indenture, these notes permit restricted payments after passing particular financial tests. The Partnership can incur debt up to $100 million for acquisitions and can also pay restricted payments of $22.0 million without passing certain financial tests.

[2] In January 2014, the Partnership entered into a second amended and restated asset based revolving credit facility agreement with a bank syndicate comprised of fifteen participants, which replaced the existing revolving credit facility.

[3] The Partnership's fair value estimates of long-term debt are made at a specific point in time, based on Level 2 inputs. Due to the relatively short maturity of the revolving credit facility, the carrying amount approximates fair value.