EMPLOYEE BENEFIT PLANS - ACCUMULATED BENEFIT OBLIGATION (Details) - Pension - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 397,164	$ 360,477
Accumulated benefit obligation	352,320	319,527
Fair value of plan assets	$ 307,968	$ 288,634

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

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-Publisher FASB
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Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

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