Participation and Contributions to Multi Employer Pension Plans (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Multiemployer Plans [Line Items]
Partnership Contributions	$ 8,374	$ 8,018	$ 7,237
New England Teamsters & Trucking Industry Pension Fund
Multiemployer Plans [Line Items]
EIN / Pension Plan Number	04-6372430 / 001
Pension Protection Act Zone Status	Red	Red
FIP / RP Status Pending / Implemented	Implemented
Partnership Contributions	2,868	2,709	2,532
Surcharge Imposed	No
Westchester Teamsters Pension Fund
Multiemployer Plans [Line Items]
EIN / Pension Plan Number	13-6123973 / 001
Pension Protection Act Zone Status	Green	Green
FIP / RP Status Pending / Implemented	NA
Partnership Contributions	855	820	771
Surcharge Imposed	No
Local 553 Pension Fund
Multiemployer Plans [Line Items]
EIN / Pension Plan Number	13-6637826 / 001
Pension Protection Act Zone Status	Green	Green
FIP / RP Status Pending / Implemented	NA
Partnership Contributions	2,649	2,729	2,152
Surcharge Imposed	No
Local 463 Pension Fund
Multiemployer Plans [Line Items]
EIN / Pension Plan Number	11-1800729 / 001
Pension Protection Act Zone Status	Green	Green
FIP / RP Status Pending / Implemented	NA
Partnership Contributions	156	146	155
Surcharge Imposed	No
All Other Multiemployer Pension Plans
Multiemployer Plans [Line Items]
Partnership Contributions	$ 1,846	$ 1,614	$ 1,627

Entity Tax Identification Number Multiemployer Plan Number

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- Definition

Amount of contributions made to multiemployer plans by the employer. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450702-114947

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450691-114947

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

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- Definition

Indicate the multiemployer plan's certified zone status as currently required by the Pension Protection Act of 2006 or a subsequent amendment thereof. The zone status categories are red (critical status), orange (seriously endangered), yellow (endangered), and green (none of the above). The acceptable values are "red", "orange", "yellow", "green", "other", and "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

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- Definition

Indicate whether a funding improvement plan or rehabilitation plan has been implemented or is pending for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "pending", "implemented", "other", and "NA".

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (f)(1)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

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- Definition

Indicate whether the employer paid a surcharge to the pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "yes", and "NA".

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (f)(2)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

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