GOODWILL AND OTHER INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Sep. 30, 2019
GOODWILL AND OTHER INTANGIBLE ASSETS
Goodwill	$ 389,942	$ 390,256
Less: accumulated amortization	123,812	107,247
Patents
GOODWILL AND OTHER INTANGIBLE ASSETS
Gross carrying amount	2,079	1,945
Less: accumulated amortization	832	748
Net	1,247	1,197
Capitalized software
GOODWILL AND OTHER INTANGIBLE ASSETS
Gross carrying amount	85,528	78,962
Less: accumulated amortization	55,315	48,530
Net	30,213	30,432
Customer relationships
GOODWILL AND OTHER INTANGIBLE ASSETS
Gross carrying amount	227,095	227,225
Less: accumulated amortization	64,562	55,326
Net	162,533	171,899
Other
GOODWILL AND OTHER INTANGIBLE ASSETS
Gross carrying amount	5,129	5,441
Less: accumulated amortization	3,105	2,645
Net	2,024	2,796
Trade names
GOODWILL AND OTHER INTANGIBLE ASSETS
Trade names	$ 174,083	$ 175,281

For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
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Gross carrying amount before accumulated amortization as of the balance sheet date to an asset acquired in a business combination representing a favorable existing relationship with customers having a finite beneficial life.

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-Publisher FASB
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-Topic 350
-SubTopic 30
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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Name Accounting Standards Codification
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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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Gross carrying amount before accumulated amortization as of the balance sheet date of the costs pertaining to the exclusive legal rights granted to the owner of the patent to exploit an invention or a process for a period of time specified by law. Such costs may have been expended to directly apply and receive patent rights, or to acquire such rights.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through registration of a trade name to gain or protect exclusive use thereof for a projected indefinite period of benefit.

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