Intangible Assets Subject to Amortization (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 348,801	$ 328,769
Accum. Amortization	241,484	227,986
Net	107,317	100,783
Customer Lists
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	322,027	304,699
Accum. Amortization	236,438	224,215
Net	85,589	80,484
Trade Names And Other Intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	26,774	24,070
Accum. Amortization	5,046	3,771
Net	$ 21,728	$ 20,299

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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