XML 13 R1.htm IDEA: XBRL DOCUMENT v3.22.0.1
Document And Entity Information - USD ($)
12 Months Ended
Dec. 31, 2021
Mar. 04, 2022
Jun. 30, 2021
Document Information [Line Items]      
Entity Central Index Key 0000884269    
Entity Registrant Name ALPHA PRO TECH LTD    
Amendment Flag false    
Current Fiscal Year End Date --12-31    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2021    
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2021    
Document Transition Report false    
Entity File Number 001-15725    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 63-1009183    
Entity Address, Address Line One 60 Centurian Drive, Suite 112    
Entity Address, City or Town Markham    
Entity Address, State or Province ON    
Entity Address, Postal Zip Code L3R 9R2    
City Area Code 905    
Local Phone Number 479-0654    
Title of 12(b) Security Common Stock, $0.01 par value    
Trading Symbol APT    
Security Exchange Name NYSE    
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    
Entity Shell Company false    
Entity Public Float     $ 101,367,511
Entity Common Stock, Shares Outstanding   13,139,391  
Auditor Name Tanner LLC    
Auditor Location Lehi, Utah    
Auditor Firm ID 270    
ICFR Auditor Attestation Flag true