OTHER COMPREHENSIVE INCOME (LOSS)- Total comprehensive income (loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Equity [Abstract]
Net income	$ 6,095	$ 5,122	$ 14,691	$ 12,593
Other comprehensive income (loss), net of taxes	12,420	(30,019)	8,442	(46,202)
Comprehensive loss	$ 18,515	$ (24,897)	$ 23,133	$ (33,609)