Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Nov. 30, 2020	Feb. 12, 2021	May 31, 2020
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Period End Date	Nov. 30, 2020
Document Transition Report	false
Entity File Number	1-35447
Entity Registrant Name	TRILOGY METALS INC.
Entity Incorporation, State or Country Code	A1
Entity Tax Identification Number	98-1006991
Entity Address, Address Line One	Suite 1150, 609 Granville Street
Entity Address, City or Town	Vancouver
Entity Address, State or Province	BC
Entity Address, Country	CA
Entity Address, Postal Zip Code	V7Y 1G5
City Area Code	604
Local Phone Number	638-8088
Title of 12(b) Security	Common Shares, no par value
Trading Symbol	TMQ
Security Exchange Name	NYSEAMER
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		144,185,729
Current Fiscal Year End Date	--11-30
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Central Index Key	0001543418
Amendment Flag	false
Entity Public Float			$ 173.0