Intangible Assets Subject to Amortization (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 329,755	$ 328,769
Accum. Amortization	231,312	227,986
Net	98,443us-gaap_FiniteLivedIntangibleAssetsNet	100,783us-gaap_FiniteLivedIntangibleAssetsNet
Customer Lists
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	305,685	304,699
Accum. Amortization	227,226	224,215
Net	78,459	80,484
Trade Names And Other Intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	24,070	24,070
Accum. Amortization	4,086	3,771
Net	$ 19,984	$ 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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