ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016	Sep. 30, 2016
Changes in foreign currency translation
Beginning accumulated foreign currency translation	$ 836	$ 663	$ 906	$ 819
Change in cumulative translation adjustment before reclassifications	22	272	(48)	116
Income taxes	0	0	0	0
Net current period other comprehensive income (loss)	22	272	(48)	116
Ending accumulated foreign currency translation	858	935	858	935
Changes in retirement plans
Beginning accumulated retirement plans benefit cost	(4,729)	(2,902)	(4,826)	(2,941)
Amortization of net actuarial loss and prior service cost	96	38	193	77
Income taxes	0	0	0	0
Net current period other comprehensive income	96	38	193	77
Ending accumulated retirement plans benefit cost	(4,633)	(2,864)	(4,633)	(2,864)
Accumulated other comprehensive loss, net of taxes	$ (3,775)	$ (1,929)	$ (3,775)	$ (1,929)	$ (3,920)