Statistical Measurement [Domain] Statistical Measurement [Domain] Business Combination [Abstract] Award Timing Predetermined Award Timing Predetermined [Flag] Related Party Transaction [Axis] Related Party Transaction [Axis] Entity File Number Entity File Number Additional Paid-In Capital Additional Paid-in Capital [Member] Credit Facility Credit Facility [Member] Represents a revolving credit facility agreement. Tabular List, Table Tabular List [Table Text Block] Recent Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Accounts payable Increase (Decrease) in Accounts Payable Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Basic earnings per share (in dollars per share) Basic EPS (in dollars per share) Earnings Per Share, Basic Adjustment to Compensation: Adjustment to Compensation [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Stream inventory Inventory, Gross Highlander Silver Corp Highlander Silver Corp [Member] Highlander Silver Corp MOUNT MILLIGAN DEFERRED LIABILITY REVENUE Revenue from Contract with Customer [Text Block] Other comprehensive loss Other Comprehensive Income (Loss), Net of Tax Schedule of Reportable Segments for Assessing Performance Schedule of Segment Reporting Information, by Segment [Table Text Block] Adjustment to Compensation, Amount Adjustment to Compensation Amount Summary of Significant Accounting Policies Consolidation, Policy [Policy Text Block] Non-cash employee stock compensation expense Share-Based Payment Arrangement, Noncash Expense Interest and other expense Interest and other expense Interest and Other Expense The cost of borrowed funds accounted for as interest that was charged against earnings during the period and other expenses not previously classified. Employee Stock Option Share-Based Payment Arrangement, Option [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Cash calls for Hod Maden equity method investment Payments to Acquire Equity Method Investments Total Royal Gold stockholders’ equity Equity, Attributable to Parent Debt Securities, Available-for-Sale [Table] Debt Securities, Available-for-Sale [Table] Adjustments to comprehensive income, net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Insider Trading Policies and Procedures [Line Items] Total stock-based compensation expense Share-Based Payment Arrangement, Expense Common stock, shares authorized (in shares) Common Stock, Shares Authorized Total liabilities and equity Liabilities and Equity Cover [Abstract] Cover [Abstract] Maximum Maximum [Member] Equity Method Investment [Table] Equity Method Investment [Table] Net income attributable to non-controlling interests Net Income (Loss) Attributable to Noncontrolling Interest Accounting Policies [Abstract] Accounting Policies [Abstract] Restricted stock Restricted Stock [Member] Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Long-term debt disclosure Debt Instrument [Line Items] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Pay vs Performance Disclosure [Line Items] Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount LIABILITIES Liabilities [Abstract] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Entity Shell Company Entity Shell Company Entree Resources Ltd. Entree Resources Ltd. [Member] Entree Resources Ltd. Other liabilities Other Liabilities, Noncurrent Schedule of Long-Term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Bear Creek Bear Creek [Member] Bear Creek Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Company Selected Measure Amount Company Selected Measure Amount Other Other interest [Member] Represents mines, other than those elsewhere enumerated, in which the entity has royalty interests. Comprehensive income attributable to non-controlling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Comprehensive income attributable to Royal Gold stockholders Comprehensive Income (Loss), Net of Tax, Attributable to Parent Royalty receivables Royalty Receivables The total amount due to the entity within one year of the balance sheet date relating to royalty contracts. Name Measure Name Distributions to non-controlling interests Payments to Noncontrolling Interests Mercedes Mine Mercedes Mine [Member] Mercedes Mine Deferred tax liabilities Deferred Income Tax Liabilities, Net Gain on sale of marketable securities Gain on sale of marketable securities Marketable Security, Realized Gain (Loss) Document Fiscal Period Focus Document Fiscal Period Focus Award Timing Method Award Timing Method [Text Block] Award Type Award Type [Axis] Mount Milligan deferred liability (Note 7) Value of cash consideration Contract with Customer, Liability, Noncurrent Paul Libner [Member] Paul Libner Legal Entity [Axis] Legal Entity [Axis] Total assets Assets Investment, Name [Domain] Investment, Name [Domain] Trading Symbol Trading Symbol Geographical [Domain] Geographical [Domain] Stock-based compensation and related share issuances (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Ilovica Ilovica [Member] Represents information pertaining to Ilovica Project, a Euromax's Ilovica gold-copper project located in southeast Macedonia. Entity Address, City or Town Entity Address, City or Town Cash flows from operating activities: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Related party transaction, term Related Party Transaction, Term Related Party Transaction, Term Entity Emerging Growth Company Entity Emerging Growth Company Cash dividends declared per common share (in dollars per share) Common Stock, Dividends, Per Share, Declared Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Debt Securities, Available-for-Sale [Line Items] Debt Securities, Available-for-Sale [Line Items] Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Equity method investment (Note 4) Equity Method Investments Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Business Combination [Domain] Business Combination [Domain] Schedule of Stream and Royalty Interests Schedule of Stream and Royalty Interests in Mineral Properties [Table Text Block] Tabular disclosure of stream and royalty interests in mineral properties of the entity, including gross amount, accumulated depletion and net amount as of the balance sheet date. Related Party Related Party [Member] Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Schedule of Components of Income Tax Expense Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Marketable Securities Marketable Securities [Table Text Block] PEO PEO [Member] Total exploration stage interests Exploration Stage Stream And Royalty Interests [Member] Represents the exploration stage stream and royalty interests of the entity. Schedule of Disaggregated Revenue Disaggregation of Revenue [Table Text Block] Conversion ratio Investment, Convertible, Conversion Ratio Investment, Convertible, Conversion Ratio Income tax payable Accrued Income Taxes, Current Changes in assets and liabilities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Accumulated Earnings Retained Earnings [Member] Prepaid expenses and other Prepaid Expense and Other Assets, Current Interest rate, effective percentage Debt Instrument, Interest Rate, Effective Percentage Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Oil and Gas, Full Cost Method, Capitalized Cost Excluded from Amortization [Line Items] Oil and Gas, Full Cost Method, Capitalized Cost Excluded from Amortization [Line Items] Share-Based Payment Arrangement [Abstract] Share-Based Payment Arrangement [Abstract] Cash and equivalents at beginning of period Cash and equivalents at end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Income Statement [Abstract] Income Statement [Abstract] Income tax expense (Note 11) Income tax expense Income Tax Expense (Benefit) Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Accumulated Depletion Mineral Properties, Accumulated Depletion Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Product and Service [Domain] Product and Service [Domain] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Royalty revenue: Royalty Interests [Member] Represents information pertaining to the Royalty Interest segment, a reportable segment of the company. Net income Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Business Combination [Table] Business Combination [Table] Schedule of Business Combination, Recognized Asset Acquired and Liability Assumed Business Combination, Recognized Asset Acquired and Liability Assumed [Table Text Block] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Total allocated purchase price Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill, Less Noncontrolling Interest Net proceeds from Sandstorm option exercises Proceeds from Stock Options Exercised City Area Code City Area Code ACQUISITION OF SANDSTORM GOLD AND HORIZON COPPER Mergers, Acquisitions and Dispositions Disclosures [Text Block] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Hod Maden Interest Hod Maden Interest [Member] Hod Maden Interest All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Royalty interest Royalty Interest [Member] Represents information pertaining to the Royalty Interest segment, a reportable segment of the company. Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Cash flows from investing activities: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] General and administrative General and administrative expenses General and Administrative Expense Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Net cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Equity Method Investments and Joint Ventures [Abstract] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Long Lived Assets and Pre-Tax Income by Geographical Information Revenues from External Customers and Long-Lived Assets [Line Items] Subsequent Event Subsequent Event [Member] Available-for-sale equity securities Equity Securities, FV-NI Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] PEO Total Compensation Amount PEO Total Compensation Amount Long-Term Debt, Type [Axis] Long-Term Debt, Type [Axis] Net smelter return, unsecured percentage Asset Acquisition, Net Smelter Return, Unsecured, Percentage Asset Acquisition, Net Smelter Return, Unsecured, Percentage Bear Creek Convertible Debenture Bear Creek Convertible Debenture [Member] Bear Creek Convertible Debenture Equity Components [Axis] Equity Components [Axis] Convertible Debt Convertible Debt [Member] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Costs and expenses Operating Costs and Expenses [Abstract] Number of reportable segments Number of Reportable Segments OPERATIONS, SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Interest and other income Interest and other income Interest and Other Income Royalty receivables Business Combination, Recognized Asset Acquired, Receivable, Current Proceeds from debt settlement Proceeds From Debt Settlement Proceeds From Debt Settlement Other Performance Measure, Amount Other Performance Measure, Amount Entity Address, State or Province Entity Address, State or Province Dividends declared Dividends, Common Stock Related and Nonrelated Parties [Domain] Related and Nonrelated Parties [Domain] Total current liabilities Liabilities, Current Individual: Individual [Axis] Common stock dividends Payments of Ordinary Dividends, Common Stock Silver Silver [Member] Represents information pertaining to silver. Entity [Domain] Entity [Domain] Net cash provided by (used in) investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Deposit Liability [Table] Deposit Liability [Table] Document Fiscal Year Focus Document Fiscal Year Focus Project [Domain] Project [Domain] Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Repayment of debt Repayments of Long-Term Debt Effective tax rate Effective Income Tax Rate Reconciliation, Percent Entity Interactive Data Current Entity Interactive Data Current Cortez Legacy Zone Cortez Legacy Zone [Member] Cortez Legacy Zone Sandstorm and Horizon Sandstorm And Horizon [Member] Sandstorm And Horizon Weighted- average vesting period (years) Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Production taxes Production taxes Taxes, Miscellaneous North America North America [Member] SEGMENT INFORMATION Segment Reporting Disclosure [Text Block] Total marketable securities Marketable Securities Streams Exploration Stage Stream Interests [Member] Represents exploration stage stream interest of entity. Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] STREAM AND ROYALTY INTERESTS, NET STREAM AND ROYALTY INTERESTS, NET No definition available. Other Commitments [Line Items] Other Commitments [Line Items] Increase (Decrease) in Stockholders' Equity Increase (Decrease) in Stockholders' Equity [Roll Forward] Pueblo Viejo Pueblo Viejo [Member] Represents Pueblo Viejo, a mine located in the Dominican Republic. Other liabilities Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent Marketable securities (Note 5) Marketable Securities, Noncurrent Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Fair Value Disclosure of Asset and Liability Not Measured at Fair Value [Table] Fair Value, Recurring and Nonrecurring [Table] Kansanshi Kansanshi [Member] Kansanshi Depreciation, depletion and amortization Depreciation, Depletion and Amortization Income tax receivable Increase (Decrease) in Income Taxes Receivable Schedule of Unrecognized Compensation Expense Share-Based Payment Arrangement, Nonvested Award, Cost [Table Text Block] Other assets Other Assets, Noncurrent Entity Central Index Key Entity Central Index Key PEO Name PEO Name Accordion feature, higher borrowing capacity option Line of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option Line of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Acquisition of stream and royalty interests Payments to Acquire Mineral Rights Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Revolving Credit Facility Revolving Credit Facility [Member] Arrangement Duration Trading Arrangement Duration Marketable securities Business Combination, Recognized Asset Acquired, Marketable Securities, Noncurrent Business Combination, Recognized Asset Acquired, Marketable Securities, Noncurrent Segments [Axis] Segments [Axis] Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Income tax receivable Business Combination, Recognized Asset Acquired, Income Tax Receivable, Current Business Combination, Recognized Asset Acquired, Income Tax Receivable, Current Exercise Price Award Exercise Price Entity Filer Category Entity Filer Category Local Phone Number Local Phone Number Other Other [Member] Other Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Other Payment for (Proceeds from) Other Investing Activity Subsequent Event Type [Axis] Subsequent Event Type [Axis] STOCK-BASED COMPENSATION Share-Based Payment Arrangement [Text Block] Cash Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent ASSETS Assets [Abstract] Debt (Note 6) Total Long-Term Debt, Excluding Current Maturities Credit Facility [Axis] Credit Facility [Axis] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Debt Instrument [Axis] Debt Instrument [Axis] FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] Business Combination [Line Items] Business Combination [Line Items] Credit Facility [Domain] Credit Facility [Domain] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Investment, Name [Axis] Investment, Name [Axis] Sandstorm converted options exercises (in shares) Stock Issued During Period, Shares, Conversion of Convertible Securities Security Milestone Security Milestone [Member] Security Milestone Name of Property [Domain] Name of Property [Domain] Fair Value as of Grant Date Award Grant Date Fair Value Entity Registrant Name Entity Registrant Name Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Total Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] Schedule of Debt Schedule of Long-Term Debt Instruments [Table Text Block] Total equity awards granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Asset acquisition, cash paid for royalty and streaming agreements Payments For Asset Acquisition Payment For Asset Acquisition Gold Gold [Member] Total costs and expenses Costs and Expenses Unrecognized compensation expense Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Net payments from issuance of common stock Payments For Issuance Of Common Stock, Net Payments For Issuance Of Common Stock, Net Document Quarterly Report Document Quarterly Report Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Accordion feature, increase limit Line of Credit Facility, Accordion Feature, Increase Limit Line of Credit Facility, Accordion Feature, Increase Limit Copper Copper [Member] Represents information pertaining to copper. Related and Nonrelated Parties [Axis] Related and Nonrelated Parties [Axis] Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Asset Acquisition, Contingent Consideration, Type [Axis] Asset Acquisition, Contingent Consideration, Type [Axis] Asset Acquisition, Contingent Consideration, Type Royalties Exploration Stage Royalty Interests [Member] Represents the exploration stage royalty interest of the entity. Repayment of debt Repayments of Long-Term Lines of Credit Restatement Determination Date: Restatement Determination Date [Axis] Stock-based compensation and related share issuances Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture Non-PEO NEO Non-PEO NEO [Member] Interest expense, debt Interest Expense, Debt Streams Development Stage Stream Interests [Member] Represents the development stage steam interest of the entity. Name Trading Arrangement, Individual Name All Award Types Award Type [Domain] Non-controlling interests Equity, Attributable to Noncontrolling Interest Equity Awards Adjustments Equity Awards Adjustments [Member] Other Other Noncash Income (Expense) Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Disaggregation of Revenue Disaggregation of Revenue [Line Items] Compensation Amount Outstanding Recovery Compensation Amount Deposit Liability [Line Items] Deposit Liability [Line Items] Cortez CC Zone Cortez CC Zone [Member] Cortez CC Zone Schedule of Stock-based Compensation Awards Share-Based Payment Arrangement, Activity [Table Text Block] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Name Awards Close in Time to MNPI Disclosures, Individual Name Equity ownership percentage Equity Ownership, Excluding Consolidated Entity and Equity Method Investee, Percentage Australia Pacific AUSTRALIA Total production stage interests Production Stage Stream And Royalty Interests [Member] Represents the production stage stream and royalty interests of the entity. Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Cost Mineral Properties, Gross Sandstorm converted options exercises Stock Issued During Period, Value, Conversion of Convertible Securities Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Realized gain on available-for-sale debt securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax Segments [Domain] Segments [Domain] EMEA EMEA [Member] Artmin Artmin [Member] Artmin Stream interest Stream Interest [Member] Represents information pertaining to the Stream Interest segment, a reportable segment of the company. Performance stock Performance Shares [Member] Line of credit facility, remaining borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity MARKETABLE SECURITIES Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Andacollo Andacollo [Member] Represents Andacollo, a mine in which the entity has royalty interests. Stream inventory Increase (Decrease) in Inventories Minimum Minimum [Member] Stream and royalty interests Business Combination, Recognized Asset Acquired, Mineral Properties, Noncurrent Business Combination, Recognized Asset Acquired, Mineral Properties, Noncurrent Company Selected Measure Name Company Selected Measure Name Payments for advance to affiliate Payments for Advance to Affiliate DEBT Debt Disclosure [Text Block] Preferred stock, $.01 par value, 10,000,000 shares authorized; and 0 shares issued Preferred Stock, Value, Issued Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Accounts payable Accounts Payable, Current Corani Project Corani Project [Member] Corani Project Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] All Executive Categories All Executive Categories [Member] Common stock, $.01 par value, 200,000,000 shares authorized; and 84,787,272 and 84,499,692 shares outstanding, respectively Common Stock, Value, Issued Prepaid expenses and other Business Combination, Recognized Asset Acquired, Prepaid Expense and Other Asset, Current COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Diluted weighted average shares outstanding (in shares) Weighted-average shares for diluted EPS (in shares) Weighted Average Number of Shares Outstanding, Diluted Commitments and contingencies (Note 14) Commitments and Contingencies Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Business Combination [Axis] Business Combination [Axis] Comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Entity Small Business Entity Small Business Schedule of Revenue by Reportable Segment Geographically Distributed Revenue from External Customers by Geographic Areas [Table Text Block] Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Non-controlling Interests Noncontrolling Interest [Member] Document Transition Report Document Transition Report Warintza Project Stream and Royalty Warintza Project Stream and Royalty [Member] Warintza Project Stream and Royalty Other assets Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent Equity method investment, ownership percentage Equity Method Investment, Ownership Percentage Underlying Securities Award Underlying Securities Amount Equity Component [Domain] Equity Component [Domain] Document Period End Date Document Period End Date Project [Axis] Project [Axis] Schedule of Geographical Distribution of Long-lived Assets Long-Lived Assets by Geographic Areas [Table Text Block] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount INCOME TAXES Income Tax Disclosure [Text Block] Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Mount Milligan Mt. Milligan [Member] Represents Mount Milligan, a mine in which the entity has royalty interests. Scenario [Axis] Scenario [Axis] Deferred tax liabilities Business Combination, Recognized Liability Assumed, Deferred Tax Liability Total equity Balance Balance Equity, Including Portion Attributable to Noncontrolling Interest Stream and royalty interests, net (Note 3) Net Total stream and royalty interests, net Mineral Properties, Net Document Type Document Type Level 3 Fair Value, Inputs, Level 3 [Member] EARNINGS PER SHARE ("EPS") Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Additional paid-in capital Additional Paid in Capital Product and Service [Axis] Product and Service [Axis] Asset Acquisition [Domain] Asset Acquisition [Domain] Revenue (Note 8) Total revenue Revenue Revenue from Contract with Customer, Excluding Assessed Tax All Individuals All Individuals [Member] Long-Term Debt, Type [Domain] Long-Term Debt, Type [Domain] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Name Forgone Recovery, Individual Name Total current assets Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Conditional funding from acquisition Asset Acquisition, Consideration Transferred, Contingent Consideration Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Schedule of Reconciliation of Segment Gross Profit to Consolidated Income (Loss) Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] Geographical [Axis] Geographical [Axis] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Level 1 Fair Value, Inputs, Level 1 [Member] Outstanding amount Long-Term Line of Credit Net smelter return (NSR) percentage Asset Acquisition, Net Smelter Return, Percentage Asset Acquisition, Net Smelter Return, Percentage Balance (in shares) Balance (in shares) Shares, Outstanding Accounts payable Business Combination, Recognized Liability Assumed, Accounts Payable, Current Net smelter return, incremental percentage Asset Acquisition, Net Smelter Return, Incremental Increase, Percentage Asset Acquisition, Net Smelter Return, Incremental Increase, Percentage Diluted earnings per share (in dollars per share) Diluted EPS (in dollars per share) Earnings Per Share, Diluted Forecast Forecast [Member] Related party transaction, rate Related Party Transaction, Rate Other tax credit Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Title of 12(b) Security Title of 12(b) Security Equity method investment Business Combination, Recognized Asset Acquired, Equity Method Investment, Noncurrent Business Combination, Recognized Asset Acquired, Equity Method Investment, Noncurrent Foreign tax credit Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Amount Net income per share attributable to Royal Gold common stockholders: Earnings Per Share [Abstract] Earnings Per Share [Abstract] Investments, Debt and Equity Securities [Abstract] Streams Production Stage Stream Interests [Member] Represents the production stage stream interests of the entity. EQUITY METHOD INVESTMENT Equity Method Investments and Joint Ventures Disclosure [Text Block] Segment gross profit Total segment gross profit Gross Profit Award Timing Disclosures [Line Items] Principal Long-Term Debt, Gross Stream revenue: Stream interest Stream Interests [Member] Represents information pertaining to the Stream Interest segment, a reportable segment of the company. Distributions to non-controlling interests Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Investment owned, balance (in shares) Investment Owned, Balance, Shares Net income attributable to Royal Gold common stockholders Net income attributable to Royal Gold common stockholders Net Income (Loss) Attributable to Parent Subsequent Event [Table] Subsequent Event [Table] Expiration Date Trading Arrangement Expiration Date Other liabilities Increase (Decrease) in Other Operating Liabilities EQUITY Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Fair value changes in equity securities Fair value changes in equity securities Fair value changes in equity securities Equity Securities, FV-NI, Unrealized Gain (Loss) South and Central America South And Central Amercia [Member] South And Central Amercia Oil and Gas, Full Cost Method, Capitalized Cost Excluded from Amortization [Table] Oil and Gas, Full Cost Method, Capitalized Cost Excluded from Amortization [Table] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Adoption Date Trading Arrangement Adoption Date Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Royalty receivables Increase (Decrease) in Accounts Receivable Entity Current Reporting Status Entity Current Reporting Status Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Operating income Operating Income (Loss) Line of Credit Line of Credit [Member] Accumulated earnings Retained Earnings (Accumulated Deficit) Name of Property [Axis] Name of Property [Axis] Schedule of Recognized Stock-based Compensation Expense Share-Based Payment Arrangement, Cost by Plan [Table Text Block] Royalties Production Stage Royalty Interests [Member] Represents the production stage royalty interest of the entity. Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Executive Category: Executive Category [Axis] Repayments of debt Repayments of Debt Current Fiscal Year End Date Current Fiscal Year End Date Subsequent Event Type [Domain] Subsequent Event Type [Domain] Other current liabilities Business Combination, Recognized Liability Assumed, Other Liability, Current Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Statement [Table] Statement [Table] Deferred tax benefit Deferred Income Tax Expense (Benefit) Adjustments to reconcile net income to net cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Cash flows from financing activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Proceeds from the sale of marketable securities Proceeds from Sale and Maturity of Marketable Securities STREAM AND ROYALTY INTERESTS, NET Stream and Royalty Interests in Mineral Properties Disclosures [Text Block] The entire disclosure for stream and royalty interests, net in mineral properties. All Adjustments to Compensation All Adjustments to Compensation [Member] Non-controlling interests Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value Amendment Flag Amendment Flag Other Commitments [Table] Other Commitments [Table] Termination Date Trading Arrangement Termination Date Net cash used in financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Measure: Measure [Axis] Schedule of Fair Value, Assets Measured on Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Basic weighted average shares outstanding (in shares) Weighted-average shares for basic EPS (in shares) Weighted Average Number of Shares Outstanding, Basic Cost of sales (excludes depreciation, depletion and amortization) Cost of sales Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization Schedule of the Effects of Dilutive Securities on Diluted EPS Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Related Party Transaction [Domain] Related Party Transaction [Domain] Subsequent Events [Abstract] Segment Reporting [Abstract] Segment Reporting [Abstract] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Entity Tax Identification Number Entity Tax Identification Number Scenario [Domain] Scenario [Domain] Depletion Depletion Asset Acquisition [Axis] Asset Acquisition [Axis] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Asset Acquisition, Contingent Consideration, Type [Domain] Asset Acquisition, Contingent Consideration, Type [Domain] Asset Acquisition, Contingent Consideration, Type [Domain] Stock-based compensation Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares, issued (in shares) Common Stock, Shares, Issued Average sale price determination period Spot Rate Forward Contracts Average Sale Price Determination Period Represents the period of consecutive trading days under the spot rate forward contract in which the sale price is determined on the daily average spot price. Income tax receivable Income Taxes Receivable, Current Gain on sale of marketable securities Equity Securities, FV-NI, Realized Gain (Loss) Earn out basis if all goals are met (as a percent) Share Based Compensation Arrangement, by Share Based Payment Award, Percentage of Interim Earn Out as Basis for Vesting Three Percentage of third interim earn out which is a basis for vesting. Dividends payable Dividends Payable, Current Trading Arrangement: Trading Arrangement [Axis] Income tax payable Increase (Decrease) in Income Taxes Payable Total Shareholder Return Amount Total Shareholder Return Amount Total development stage interests Development Stage Stream And Royalty Interests [Member] Represents the development stage stream and royalty interests of the entity. Share repurchase Share Repurchase Program, Authorized, Amount Share Repurchase Program, Authorized, Amount SUBSEQUENT EVENTS Subsequent Events [Text Block] Insider Trading Arrangements [Line Items] Value of consideration, nonmonetary amount, gold Contract With Customer, Liability, Nonmonetary Amount, Gold Represents the quantity of gold produced or delivered under the terms of the agreement. Security Exchange Name Security Exchange Name Total liabilities Liabilities Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Other current liabilities Other Liabilities, Current Statement Statement [Line Items] Debt Issuance Costs Unamortized Debt Issuance Expense Settled debt obligations Extinguishment of Debt, Amount Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Cash and equivalents Cash and Cash Equivalent Subsequent Event [Line Items] Subsequent Event [Line Items] Common Shares Common Stock [Member] Available-for-sale debt securities Debt Securities, Available-for-Sale Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Net increase in cash and equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Effect of other dilutive securities (in shares) Weighted Average Number of Shares Outstanding, Diluted, Adjustment Royalties Development Stage Royalty Interests [Member] Represents the development stage royalty interest of the entity.