ROYALTY ACQUISITIONS (Details) (USD $)	6 Months Ended				1 Months Ended		1 Months Ended	6 Months Ended	1 Months Ended		1 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Mt. Milligan	Dec. 31, 2010 Mt. Milligan	Dec. 31, 2011 Tulsequah oz	Dec. 22, 2011 Tulsequah	Oct. 31, 2010 Milligan I Acquisition	Dec. 31, 2011 Milligan I Acquisition	Dec. 31, 2011 Milligan II Agreement subsidiary	Dec. 14, 2011 Milligan II Agreement	Dec. 31, 2011 Milligan II Agreement Thompson Creek subsidiary
Acquisition of Royalty Interest in Mineral Properties
Number of subsidiaries which entered into Milligan II Agreement									1		1
Total purchase price of royalty interests				$ 581,500,000		$ 60,000,000	$ 311,500,000			$ 270,000,000
Cash paid for acquisition of royalty interests	148,182,000	279,500,000			10,000,000		226,500,000	252,600,000	112,000,000
Percentage of payable ounces of gold purchased				40.00%			25.00%			15.00%
Cash payment for each payable ounce of gold (in dollars per ounce)				435
Future scheduled payments			216,900,000
Future scheduled payments for each quarter in calendar year 2012			45,000,000
Aggregate future scheduled payments for calendar year 2012			180,000,000
Future scheduled payments for first two quarters in calendar year 2013			12,000,000
Future scheduled payments for third quarter in calendar year 2013			12,900,000
Aggregate future scheduled payments for calendar year 2013			36,900,000
Maximum future additional payments upon satisfaction of certain conditions in the Tulsequah Agreement					50,000,000
Percentage of produced payable gold to be purchased until 48,000 ounces have been delivered					12.50%
Maximum cash payment for each payable ounce of gold until 48,000 ounces have been delivered (in dollars per ounce)					450
Maximum quantity of gold with maximum cash payment of $450 per ounce (in ounces)					48,000
Percentage of produced payable gold to be purchased after 48,000 ounces have been delivered					7.50%
Maximum cash payment for each payable ounce of gold after 48,000 ounces have been delivered (in dollars per ounce)					500
Percentage of produced payable silver to be purchased until 2,775,000 ounces have been delivered					22.50%
Maximum cash payment for each payable ounce of silver until 2,775,000 ounces have been delivered (in dollars per ounce)					5.00
Maximum quantity of silver with maximum cash payment of $5.00 per ounce (in ounces)					2,775,000
Percentage of produced payable silver to be purchased after 2,775,000 ounces have been delivered					9.75%
Maximum cash payment for each payable ounce of silver after 2,775,000 ounces have been delivered (in dollars per ounce)					$ 7.50
Streaming percentage for payable gold and payable silver upon suspension of obligations					6.50%