SUBSEQUENT EVENT (Details) (Subsequent event, El Morro, USD $) In Millions, unless otherwise specified	Aug. 31, 2013
Goldcorp Inc.
Subsequent Event
Ownership interest in Mineral Property (as a percent)	70.00%
Chilean subsidiary
Subsequent Event
Percentage of royalty interests acquired or agreed to be acquired	70.00%
Royalty interests in Mineral Property, net (as a percent)	2.00%
Total purchase amount	$ 35.0
New Gold Inc.
Subsequent Event
Ownership interest in Mineral Property (as a percent)	30.00%