Intangible Assets Subject to Amortization (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 352,592	$ 348,801
Accum. Amortization	249,105	241,484
Net	103,487	107,317
Customer Lists
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	325,594	322,027
Accum. Amortization	243,365	236,438
Net	82,229	85,589
Trade Names And Other Intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	26,998	26,774
Accum. Amortization	5,740	5,046
Net	$ 21,258	$ 21,728

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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