EMPLOYEE BENEFIT PLANS, AMOUNTS EXPECTED TO BE RECOGNIZED IN NET PERIODIC BENEFIT COST (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2015 USD ($)
Pension [Member]
Regulatory Assets
Net actuarial loss	$ 5,606
Prior service cost (credit)	108
Total	5,714
Accumulated Other Comprehensive Income (Loss)
Net actuarial loss	1,675
Prior service cost (credit)	3
Total	1,678
OPEB [Member]
Regulatory Assets
Net actuarial loss	3,175
Prior service cost (credit)	(311)
Total	2,864
Accumulated Other Comprehensive Income (Loss)
Net actuarial loss	99
Prior service cost (credit)	(54)
Total	$ 45