Note 12 - Business Segment Information - Segment Activity (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 02, 2017	Mar. 27, 2016	Dec. 31, 2016
Revenues	$ 22,035	$ 20,833
Segment contribution	1,841	482
Interest, financing and miscellaneous expense, net	(93)	(113)
Tax provision	(87)	(88)
Non-Controlling interest	(6)	18
Net income attributable to Ultralife	1,655	299
Total assets	87,582	85,643	$ 84,744
Battery & Energy Products Segment [Member]
Revenues	17,479	16,440
Segment contribution	4,930	5,217
Total assets	39,734	46,898
Communications Systems Segment [Member]
Revenues	4,556	4,393
Segment contribution	1,960	1,188
Total assets	32,039	33,720
Corporate Segment [Member]
Revenues
Segment contribution	(5,049)	(5,924)
Interest, financing and miscellaneous expense, net	(93)	(113)
Tax provision	(87)	(88)
Non-Controlling interest	(6)	18
Total assets	$ 15,809	$ 5,025

Represents the net amount of interest and other finance costs during the period.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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