RELINQUISHMENT AGREEMENT (Details) - USD ($)		3 Months Ended		9 Months Ended
	Jan. 01, 2000	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Sep. 30, 2014	Sep. 30, 1998
RELINQUISHMENT AGREEMENT [Abstract]
Term of relinquishment agreement	15 years
Relinquishment liability		$ 0		$ 0		$ 25,200,000	$ 549,100,000
Relinquishment liability reassessment		0	$ 0	243,000	$ 0
Accretion of discount to the relinquishment liability		0	$ 552,000	227,000	1,654,000
Relinquishment Payments [Abstract]
Principal				24,400,000	29,129,000
Accretion of discount				778,000	2,071,000
Total relinquishment payments				25,200,000	$ 31,200,000
Accrued relinquishment payments		$ 0		$ 0		$ 13,200,000