RETIREMENT PLANS - FAIR VALUE (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Pension plan assets at the fair value
Fair value measurements	$ 12,594	$ 11,051
Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	12,594	11,051
Significant Other Observable Inputs (Level 2)
Pension plan assets at the fair value
Fair value measurements	0	0
Significant Unobservable Inputs (Level 3)
Pension plan assets at the fair value
Fair value measurements	0	0
Cash
Pension plan assets at the fair value
Fair value measurements	25
Cash | Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	25
Cash | Significant Other Observable Inputs (Level 2)
Pension plan assets at the fair value
Fair value measurements	0
Cash | Significant Unobservable Inputs (Level 3)
Pension plan assets at the fair value
Fair value measurements	0
Corporate bonds
Pension plan assets at the fair value
Fair value measurements	1	1
Corporate bonds | Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	1	1
Corporate bonds | Significant Other Observable Inputs (Level 2)
Pension plan assets at the fair value
Fair value measurements	0	0
Corporate bonds | Significant Unobservable Inputs (Level 3)
Pension plan assets at the fair value
Fair value measurements	0	0
Fixed income exchange-traded funds
Pension plan assets at the fair value
Fair value measurements	3,809	5,762
Fixed income exchange-traded funds | Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	3,809	5,762
Fixed income exchange-traded funds | Significant Other Observable Inputs (Level 2)
Pension plan assets at the fair value
Fair value measurements	0	0
Fixed income exchange-traded funds | Significant Unobservable Inputs (Level 3)
Pension plan assets at the fair value
Fair value measurements	0	0
Preferred securities
Pension plan assets at the fair value
Fair value measurements	48
Preferred securities | Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	48
Preferred securities | Significant Other Observable Inputs (Level 2)
Pension plan assets at the fair value
Fair value measurements	0
Preferred securities | Significant Unobservable Inputs (Level 3)
Pension plan assets at the fair value
Fair value measurements	0
Equity securities exchange-traded funds
Pension plan assets at the fair value
Fair value measurements	459	352
Equity securities exchange-traded funds | Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	459	352
Equity securities exchange-traded funds | Significant Other Observable Inputs (Level 2)
Pension plan assets at the fair value
Fair value measurements	0	0
Equity securities exchange-traded funds | Significant Unobservable Inputs (Level 3)
Pension plan assets at the fair value
Fair value measurements	0	0
Equities
Pension plan assets at the fair value
Fair value measurements	8,252	4,936
Equities | Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	8,252	4,936
Equities | Significant Other Observable Inputs (Level 2)
Pension plan assets at the fair value
Fair value measurements	0	0
Equities | Significant Unobservable Inputs (Level 3)
Pension plan assets at the fair value
Fair value measurements	$ 0	$ 0