v3.26.1
Note 10 - Business Segment Information - Segment Activity (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Revenues $ 47,943 $ 48,561 $ 95,388 $ 99,307  
Cost of products sold (34,077) (36,960) (71,412) (74,961)  
Gross profit 13,866 11,601 23,976 24,346  
Operating Expenses 10,429 9,345 20,754 18,691  
Research and development (3,225) (2,318) (6,186) (4,722)  
Segment contribution 3,437 2,256 3,222 5,655  
Operating Income 3,437 2,256 3,222 5,655  
Other expenses, net (451) (1,143) (899) (2,096)  
Income tax provision (468) (243) (276) (810)  
Non-controlling interest 25 9 45 (5)  
Net income attributable to Ultralife 2,543 879 2,092 2,744  
Total assets 216,157 220,961 216,157 220,961 $ 216,912
Depreciation and amortization of intangible assets 1,324 1,418 2,645 2,773  
Battery & Energy Products Segment [Member]          
Operating Expenses (4,705)   (9,165)    
Operating Segments [Member]          
Operating Expenses   (4,408)   (8,639)  
Segment contribution 5,936 4,875 8,625 10,985  
Operating Income 5,936 4,875 8,625 10,985  
Operating Segments [Member] | Battery & Energy Products Segment [Member]          
Revenues 44,189 45,867 88,344 92,188  
Cost of products sold (31,686) (35,032) (66,483) (69,913)  
Gross profit 12,503 10,835 21,861 22,275  
Operating Expenses (4,387) (4,024) (8,468) (7,889)  
Research and development (2,303) (1,494) (4,525) (3,085)  
Segment contribution 5,813 5,317 8,868 11,301  
Operating Income 5,813 5,317 8,868 11,301  
Total assets 169,060 170,705 169,060 170,705  
Depreciation and amortization of intangible assets 1,161 1,321 2,383 2,586  
Operating Segments [Member] | Communications Systems Segment [Member]          
Revenues 3,754 2,694 7,044 7,119  
Cost of products sold (2,391) (1,928) (4,929) (5,048)  
Gross profit 1,363 766 2,115 2,071  
Operating Expenses (318) (384) (697) (750)  
Research and development (922) (824) (1,661) (1,637)  
Segment contribution 123 (442) (243) (316)  
Operating Income 123 (442) (243) (316)  
Total assets 26,969 28,330 26,969 28,330  
Depreciation and amortization of intangible assets 49 58 106 116  
Segment Reporting, Reconciling Item, Corporate Nonsegment [Member]          
Revenues 0 0 0 0  
Cost of products sold 0 0 0 0  
Gross profit 0 0 0 0  
Research and development 0 0 0 0  
Other expenses, net (451) (1,143) (899) (2,096)  
Income tax provision (468) (243) (276) (810)  
Non-controlling interest 25 9 45 (5)  
Total assets 20,128 21,926 20,128 21,926  
Depreciation and amortization of intangible assets $ 114 $ 39 $ 156 $ 71