MAJOR SOURCES OF REVENUE (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2011
MAJOR SOURCES OF REVENUE
Minimum percentage required for qualifying as major operator	10.00%
Teck | Royalty revenue | Concentration of risk by operator
Major sources of revenue
Royalty revenue	$ 82,272	$ 64,075	$ 43,604
Percentage of total royalty revenue	28.40%	24.40%	20.10%
Vale Newfoundland & Labrador Limited | Royalty revenue | Concentration of risk by operator
Major sources of revenue
Royalty revenue	32,517	36,030	32,677
Percentage of total royalty revenue	11.20%	13.70%	15.10%
Goldcorp, Inc. | Royalty revenue | Concentration of risk by operator
Major sources of revenue
Royalty revenue	32,461	31,407	23,094
Percentage of total royalty revenue	11.20%	11.90%	10.70%
Barrick Gold | Royalty revenue | Concentration of risk by operator
Major sources of revenue
Royalty revenue	$ 22,943	$ 21,891	$ 26,843
Percentage of total royalty revenue	7.90%	8.30%	12.40%