Note 12 - Business Segment Information - Segment Activity (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 26, 2016	Jun. 28, 2015	Jun. 26, 2016	Jun. 28, 2015	Dec. 31, 2015
Battery & Energy Products Segment [Member]
Revenues	$ 15,759	$ 15,972	$ 32,199	$ 32,248
Segment Contribution	4,664	4,542	9,881	9,326
Total Assets	44,475	37,084	44,475	37,084
Communications Systems Segment [Member]
Revenues	4,612	2,983	9,005	5,884
Segment Contribution	1,236	1,317	2,424	2,540
Total Assets	33,489	27,906	33,489	27,906
Corporate Segment [Member]
Revenues
Segment Contribution	(5,401)	(5,042)	(11,324)	(10,227)
Interest, Financing and Miscellaneous Expense, Net	(24)	28	(137)	(160)
Tax Provision	(33)	(71)	(121)	(182)
Non-Controlling Interest	4	14	22	24
Total Assets	5,334	17,945	5,334	17,945
Revenues	20,371	18,955	41,204	38,132
Segment Contribution	499	817	981	1,639
Interest, Financing and Miscellaneous Expense, Net	(24)	28	(137)	(160)
Tax Provision	(33)	(71)	(121)	(182)
Non-Controlling Interest	4	14	22	24
Net Income Attributable to Ultralife	446	788	745	1,321
Total Assets	$ 83,298	$ 82,935	$ 83,298	$ 82,935	$ 81,522

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.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of Net Income (Loss) attributable to noncontrolling interest.

+ References

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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).

+ References

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