v3.26.1
Cover Page - shares
6 Months Ended
Jun. 30, 2026
Aug. 03, 2026
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2026  
Document Transition Report false  
Entity File Number 001-40136  
Entity Registrant Name Amalgamated Financial Corp.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 85-2757101  
Entity Address, Address Line One 275 Seventh Avenue  
Entity Address, City or Town New York  
Entity Address, State or Province NY  
Entity Address, Postal Zip Code 10001  
City Area Code 212  
Local Phone Number 255-6200  
Title of 12(b) Security Common Stock, par value $0.01 per share  
Trading Symbol AMAL  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Accelerated Filer  
Smaller Reporting Company false  
Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding (in shares)   29,900,147
Entity Central Index Key 0001823608  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q2  
Amendment Flag false