OTHER LONG-TERM ASSETS (Details) $ in Thousands	9 Months Ended
	Jun. 30, 2016 USD ($) Security	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)
Other long-term assets [Abstract]
Auction rate securities (ARS)	$ 5,494	$ 5,694
Other long-term assets	3,648	3,595
Long-term contract asset	3,290	3,995
Other long-term investments	979	1,720
Total	$ 13,411	$ 15,004
Number of auction rate securities | Security	2
Minimum maturity period of auction rate securities (ARS)	10 years
Fair value of auction rate securities	$ 4,981
Gross unrecognized loss of ARS	513
Long-term contract asset face amount			$ 4,500
Long-term liability, SERP investments	$ 979