FAIR VALUE OF FINANCIAL INSTRUMENTS - Fair Value Disclosure (Details) - Fair value, measurements, recurring - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Assets:
Cash and cash equivalents	$ 257,354	$ 188,495
Other long-term investments	1,214	980
Derivative financial instruments	27
Liabilities:
Derivative financial instruments	38,157	24,244
Level 1
Assets:
Cash and cash equivalents	257,354	188,495
Other long-term investments	1,214	980
Derivative financial instruments	0
Liabilities:
Derivative financial instruments	0	0
Level 2
Assets:
Cash and cash equivalents	0	0
Other long-term investments	0	0
Derivative financial instruments	27
Liabilities:
Derivative financial instruments	38,157	24,244
Level 3
Assets:
Cash and cash equivalents	0	0
Other long-term investments	0	0
Derivative financial instruments	0
Liabilities:
Derivative financial instruments	$ 0	$ 0

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
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-Publisher FASB
-Name Accounting Standards Codification
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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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