ROYALTY PORTFOLIO RESTRUCTURING GAIN (Details) (USD $)	12 Months Ended			3 Months Ended	1 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2009	Dec. 31, 2008 Cortez	May 31, 2009 Benso 1.5% NSR royalty	Dec. 31, 2007 Benso 1.5% NSR royalty
Royalty portfolio restructuring gain
Gain on royalty restructuring			$ 33,714,000	$ 31,500,000	$ 2,200,000
Percentage of Royalty Repurchased by Third Party					1.50%
Proceeds from royalty restructuring			34,897,000		3,400,000
Cash paid for acquisition of royalty interests	280,009,000	232,996,000	186,110,000			1,900,000
Net book value of royalty	$ 1,690,439,000	$ 1,476,799,000			$ 1,200,000