Note 5 - Mineral Properties (Details Textual) $ / shares in Units, T in Millions													1 Months Ended		12 Months Ended
		Nov. 26, 2018 shares	Nov. 15, 2018 USD ($)	Nov. 15, 2018 CAD ($)	Nov. 06, 2018 shares	Nov. 30, 2017 shares	Jun. 09, 2017 $ / shares shares	Mar. 30, 2015 USD ($)	Mar. 28, 2013 USD ($) T	Mar. 01, 2011 USD ($)	Oct. 09, 2009 USD ($)	Dec. 01, 2007 USD ($)	Dec. 31, 2013 USD ($) a	Dec. 31, 2013 CAD ($) a	May 31, 2019 CAD ($)	May 31, 2018 CAD ($)	Dec. 31, 2014 shares	May 31, 2013 USD ($)	May 31, 2013 CAD ($)	May 31, 2019 USD ($)	May 31, 2019 CAD ($)	Mar. 31, 2019 USD ($)	Mar. 01, 2019 USD ($)	May 31, 2018 USD ($)	May 31, 2018 CAD ($)	May 29, 2014 USD ($)	May 31, 2013 CAD ($)	Oct. 27, 2008 USD ($)	Jun. 16, 2006 USD ($)	May 22, 2006 USD ($)	May 16, 2006 USD ($)	May 08, 2006 USD ($)
Payments to Acquire Mineral Rights	[1]														$ 47,318	$ 38,384
Asset Retirement Obligations, Noncurrent, Total																				$ 309,000	$ 419,286			$ 283,000	$ 366,641
North Bullfrog [Member]
Unpatented Mineral Claims															100.00%
Capital Leases, Future Minimum Payments, Remainder of Fiscal Year											$ 39,800
Capital Leases, Future Minimum Payments Due Thereafter											$ 17,700
Number of Patented Mining Claims, Available to Purchase																												12
Payments to Acquire Mineral Rights	[1],[2]														$ 47,318	38,384
Land Subject to Ground Leases | a													1,600	1,600
North Bullfrog [Member] | Nevada Corporation [Member]
Net Smelter Return, Royalty Percentage of Production																										3.00%						3.00%
Purchase Price of Each 1% NSR Royalty																										$ 770,000						$ 850,000
Purchase Price of NSR Royalty																										$ 2,310,000						$ 2,550,000
North Bullfrog [Member] | Redstar Gold Corp. [Member]
Number of Leases											6
Number of Patented Mining Claims Leased											33
Mining Lease Agreement Term of Contract											10 years
Net Smelter Return, Royalty Percentage of Production																												4.00%	2.00%	2.00%	4.00%	2.00%
Purchase Price of Each 1% NSR Royalty																												$ 1,250,000	$ 1,000,000	$ 1,000,000	$ 1,000,000	$ 1,000,000
Purchase Price of NSR Royalty																												$ 5,000,000	$ 2,000,000	$ 2,000,000	$ 4,000,000	$ 2,000,000
North Bullfrog [Member] | Corvus Gold Nevada Inc. [Member]
Number of Patented Mining Claims Leased										2
Mining Lease Agreement Term of Contract										10 years
Net Smelter Return, Royalty Percentage of Production								4.00%		2.00%
Purchase Price of Each 1% NSR Royalty								$ 500,000		$ 1,000,000
Purchase Price of NSR Royalty								$ 2,000,000		$ 2,000,000
Lease Term								3 years				5 years
Additional Lease Term								7 years				5 years
Mining Lease Agreement Term of Contract, Extension Term										10 years		10 years
Lease Payment for Patended Mining Claims Upon Extend Lease			$ 10,000
Lease Payment for Patented Mining Claims Lease			$ 10,000
Lease Payments Common Shares Issued | shares																	25,000
Cash Payment Along with Shares Issued as Lease Payment				$ 34,116
Work Commitments for the First Three Year												$ 100,000
Work Commitments for the Years 4 to 6												200,000
Work Commitments for the years 7 to 10												300,000
Work Commitments for the years 11 to 20												$ 300,000
Percentage of NSR Royalty Required to Pay If Average Gold Price Less than or Equal to USD400 per Ounce												2.00%
Percentage of NSR Royalty Required to Pay If Average Gold Price Between USD401 and USD500 per Ounce												3.00%
Percentage of NSR Royalty Required to Pay if Average Gold Price Greater than USD500 per Ounce												4.00%
Advance Royalties Payment								$ 5,000														$ 5,000	$ 30,000
Patented Mining Claims, Agreed to Purchase									5
Purchase Agreement Payable									$ 160,000
Price Per Ton Of Overburden to be Stored On Property									0.02
Minimum Storage Capacity of Property | T									12
Notes Payable, Total									$ 240,000									$ 240,000									$ 248,832
Acquisition Costs, Period Cost																		$ 400,000	$ 406,240
Payments to Acquire Mineral Rights																			$ 157,408
Number of Patented Sunflower Claims								3
Lease Agreement, Option to Purchase Property, Purcahse Price								$ 300,000
Stock Issued During Period, Shares, Acquisitions | shares		25,000				25,000
North Bullfrog [Member] | Corvus Gold Nevada Inc. [Member] | Promissory Note Payable [Member]
Debt Instrument, Interest Rate, Effective Percentage									4.77%
North Bullfrog [Member] | International Tower Hill Mines Ltd. [Member]
Lease Payments Common Shares Issued Upon Extend Lease | shares					50,000
Lease Payments Common Shares Issued | shares					50,000
Land and Water Rights [Member]
Payments to Acquire Mineral Rights													$ 1,034,626	$ 1,100,118
Mother Lode Property [Member]
Payments to Acquire Mineral Rights	[3]
Stock Issued During Period, Shares, Acquisitions | shares							1,000,000
Mother Lode Property [Member] | Goldcorp USA, Inc [Member]
Stock Issued During Period, Shares, Acquisitions | shares							1,000,000
Shares Issued, Price Per Share | $ / shares							$ 0.81
Mother Lode Property [Member] | Goldcorp USA, Inc [Member]
Net Smelter Return, Royalty Percentage of Production Based on Specified Maximum Gold Price							1.00%
Net Smelter Return, Maximum Gold Price							1,400
Net Smelter Return, Additional Royalty Percentage of Production Based on Specified Minimum Gold Price							1.00%
Net Smelter Return, Total Royalty Percentage of Production							2.00%
Net Smelter Return, Minimum Gold Price							1,400

[1] Pursuant to a mining lease and option to purchase agreement made effective December 1, 2007 between Corvus Nevada and a group of arm's length limited partnerships, Corvus Nevada has leased (and has the option to purchase) patented mining claims referred to as the "Mayflower" claims which form part of the North Bullfrog project. The terms of the lease/option are as follows: Terms: Initial term of five years, commencing December 1, 2007, with the option to extend the lease for an additional five years. Pursuant to an extension agreement dated January 15, 2016 and fully executed and effective as of November 22, 2017, the parties agreed to extend the lease and option granted for an additional ten years with the same lease payment terms. Lease Payments: Corvus Nevada will pay USD 10,000 and deliver 50,000 common shares of ITH (USD 10,000 paid on November 15, 2018 and 50,000 common shares of ITH, purchased for $34,116 in the market by the Company, were delivered on November 6, 2018). Anti-Dilution: Pursuant to an amended agreement agreed to by the lessors in March 2015, the Company, all future payments will be satisfied by the delivery of an additional 1/2 common shares of the Company for each of the ITH common shares due per the original agreement (issued 25,000 shares of the Company on November 26, 2018). Work Commitments: USD 100,000 per year for the first three years (incurred), USD 200,000 per year for the years four to six (incurred), USD 300,000 for the years seven to ten (incurred) and USD 300,000 for the years 11 - 20 (incurred). Excess expenditures in any year may be carried forward. If Corvus Nevada does not incur the required expenditures in year one, the deficiency is required to be paid to the lessors. Retained Royalty: Corvus Nevada will pay the lessors a NSR royalty of 2% if the average gold price is USD 400 per ounce or less, 3% if the average gold price is between USD 401 and USD 500 per ounce and 4% if the average gold price is greater than USD 500 per ounce.

[2] The Company's North Bullfrog project consists of certain leased patented lode mining claims and federal unpatented mining claims owned 100% by the Company.

[3] Pursuant to a purchase agreement made effective June 9, 2017 between Corvus Nevada and Goldcorp USA, Inc. ("Goldcorp USA"), Corvus Nevada has acquired 100% of the Mother Lode property (the "Mother Lode Property"). In addition, Corvus Nevada staked two additional adjacent claim blocks to the Mother Lode Property. In connection with the acquisition, the Company issued 1,000,000 common shares at a price of $0.81 per common share to Goldcorp USA (note 6). The Mother Lode Property is subject to an NSR in favour of Goldcorp USA. The NSR pays 1% from production at the Mother Lode Property when the price of gold is less than USD 1,400 per ounce and an additional 1% NSR for a total of 2% NSR when gold price is greater than or equal to USD 1,400 per ounce.