EMPLOYEE BENEFIT PLANS - Fair Value of Pension Plan Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jan. 16, 2025	Sep. 30, 2024	Sep. 30, 2023
United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	$ 48,550		$ 53,521	$ 43,780
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	35,128	$ 33,200	0
Estimate of Fair Value Measurement \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	48,550		53,521
Estimate of Fair Value Measurement \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			35,152
Estimate of Fair Value Measurement \| Short-term investments \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	201		3,369
Estimate of Fair Value Measurement \| Mutual funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	48,322		50,060
Estimate of Fair Value Measurement \| Domestic stock funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	2,218		5,223
Estimate of Fair Value Measurement \| Bond funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	43,489		41,950
Estimate of Fair Value Measurement \| International stock funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	2,615		2,887
Estimate of Fair Value Measurement \| Oil and gas properties \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	27		92
Estimate of Fair Value Measurement \| International equities \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			3,674
Estimate of Fair Value Measurement \| Diversified Growth Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			4,636
Estimate of Fair Value Measurement \| Gilts (UK government bonds) \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			1,359
Estimate of Fair Value Measurement \| Corporate bonds \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			817
Estimate of Fair Value Measurement \| Strategic Income Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			4,729
Estimate of Fair Value Measurement \| Liability-Driven Investments (LDI) \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			9,365
Estimate of Fair Value Measurement \| Absolute Return Credit Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			8,734
Estimate of Fair Value Measurement \| Cash \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			1,838
Estimate of Fair Value Measurement \| Level 1 \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	48,523		53,429
Estimate of Fair Value Measurement \| Level 1 \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			6,871
Estimate of Fair Value Measurement \| Level 1 \| Short-term investments \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	201		3,369
Estimate of Fair Value Measurement \| Level 1 \| Mutual funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	48,322		50,060
Estimate of Fair Value Measurement \| Level 1 \| Domestic stock funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	2,218		5,223
Estimate of Fair Value Measurement \| Level 1 \| Bond funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	43,489		41,950
Estimate of Fair Value Measurement \| Level 1 \| International stock funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	2,615		2,887
Estimate of Fair Value Measurement \| Level 1 \| Oil and gas properties \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 1 \| International equities \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			3,674
Estimate of Fair Value Measurement \| Level 1 \| Diversified Growth Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 1 \| Gilts (UK government bonds) \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			1,359
Estimate of Fair Value Measurement \| Level 1 \| Corporate bonds \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 1 \| Strategic Income Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 1 \| Liability-Driven Investments (LDI) \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 1 \| Absolute Return Credit Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 1 \| Cash \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			1,838
Estimate of Fair Value Measurement \| Level 2 \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 2 \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			28,281
Estimate of Fair Value Measurement \| Level 2 \| Short-term investments \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 2 \| Mutual funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 2 \| Domestic stock funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 2 \| Bond funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 2 \| International stock funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 2 \| Oil and gas properties \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 2 \| International equities \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 2 \| Diversified Growth Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			4,636
Estimate of Fair Value Measurement \| Level 2 \| Gilts (UK government bonds) \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 2 \| Corporate bonds \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			817
Estimate of Fair Value Measurement \| Level 2 \| Strategic Income Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			4,729
Estimate of Fair Value Measurement \| Level 2 \| Liability-Driven Investments (LDI) \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			9,365
Estimate of Fair Value Measurement \| Level 2 \| Absolute Return Credit Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			8,734
Estimate of Fair Value Measurement \| Level 2 \| Cash \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 3 \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	27		92
Estimate of Fair Value Measurement \| Level 3 \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 3 \| Short-term investments \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 3 \| Mutual funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 3 \| Domestic stock funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 3 \| Bond funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 3 \| International stock funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0		0
Estimate of Fair Value Measurement \| Level 3 \| Oil and gas properties \| United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	$ 27		92
Estimate of Fair Value Measurement \| Level 3 \| International equities \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 3 \| Diversified Growth Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 3 \| Gilts (UK government bonds) \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 3 \| Corporate bonds \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 3 \| Strategic Income Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 3 \| Liability-Driven Investments (LDI) \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 3 \| Absolute Return Credit Fund \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0
Estimate of Fair Value Measurement \| Level 3 \| Cash \| Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			$ 0