Document and Entity Information - USD ($)	12 Months Ended
	Jun. 30, 2017	Aug. 01, 2017	Dec. 31, 2016
Document and Entity Information
Entity Registrant Name	ROYAL GOLD INC
Entity Central Index Key	0000085535
Document Type	10-K
Document Period End Date	Jun. 30, 2017
Amendment Flag	false
Current Fiscal Year End Date	--06-30
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 4,102,671,750
Entity Shares Outstanding		65,343,544
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY