Note 11 - Business Segment Information - Revenue by Business Segment Sector (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Revenues	$ 50,746	$ 41,927
UNITED STATES
Revenues	$ 39,469	$ 24,461
Revenue, percentage	78.00%	58.00%
Non-US [Member]
Revenues	$ 11,277	$ 17,466
Revenue, percentage	22.00%	42.00%
Commercial [Member]
Revenues	$ 29,659	$ 24,140
Revenue, percentage	58.00%	58.00%
Government & Defense [Member]
Revenues	$ 21,087	$ 17,787
Revenue, percentage	42.00%	42.00%
Battery & Energy Products Segment [Member]
Revenues	$ 46,321	$ 34,989
Battery & Energy Products Segment [Member] \| UNITED STATES
Revenues	35,182	19,603
Battery & Energy Products Segment [Member] \| Non-US [Member]
Revenues	11,139	15,386
Battery & Energy Products Segment [Member] \| Commercial [Member]
Revenues	29,659	24,140
Battery & Energy Products Segment [Member] \| Government & Defense [Member]
Revenues	16,662	10,849
Communications Systems Segment [Member]
Revenues	4,425	6,938
Communications Systems Segment [Member] \| UNITED STATES
Revenues	4,287	4,858
Communications Systems Segment [Member] \| Non-US [Member]
Revenues	138	2,080
Communications Systems Segment [Member] \| Commercial [Member]
Revenues	$ 4,425	0
Communications Systems Segment [Member] \| Government & Defense [Member]
Revenues		$ 6,938

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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+ Details

ULTRALIFE CORP 10-Q