GOODWILL AND OTHER INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
GOODWILL AND OTHER INTANGIBLE ASSETS
Goodwill	$ 411,661	$ 408,063
Less: accumulated amortization	138,928	129,063
Patents
GOODWILL AND OTHER INTANGIBLE ASSETS
Gross carrying amount	2,136	2,092
Less: accumulated amortization	915	858
Net	1,221	1,234
Capitalized software
GOODWILL AND OTHER INTANGIBLE ASSETS
Gross carrying amount	88,862	84,888
Less: accumulated amortization	60,563	57,302
Net	28,299	27,586
Customer relationships
GOODWILL AND OTHER INTANGIBLE ASSETS
Gross carrying amount	229,322	227,178
Less: accumulated amortization	73,864	67,643
Net	155,458	159,535
Other
GOODWILL AND OTHER INTANGIBLE ASSETS
Gross carrying amount	5,356	5,156
Less: accumulated amortization	3,586	3,260
Net	1,770	1,896
Trade names
GOODWILL AND OTHER INTANGIBLE ASSETS
Trade names	$ 158,513	$ 156,381

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
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-SubTopic 20
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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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-Name Accounting Standards Codification
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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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Accumulated amount of 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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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Amount before accumulated amortization of finite-lived intangible assets classified as other.

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