Note 12 - Business Segment Information - Segment Activity (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 02, 2017	Jun. 26, 2016	Jul. 02, 2017	Jun. 26, 2016	Dec. 31, 2016
Non-Controlling Interest		$ 4	$ (6)	$ 22
Net Income Attributable to Ultralife	1,094	446	2,749	745
Total Assets	90,265	83,298	90,265	83,298	$ 84,744
Revenues	19,939	20,371	41,974	41,204
Segment Contribution	1,322	499	3,163	981
Interest, Financing and Miscellaneous Expense, Net	(49)	(24)	(142)	(137)
Tax Provision	(179)	(33)	(266)	(121)
Battery & Energy Products Segment [Member]
Total Assets		44,475		44,475
Revenues	16,880	15,759	34,359	32,199
Segment Contribution	4,741	4,664	9,671	9,881
Communications Systems Segment [Member]
Total Assets		33,489		33,489
Revenues	3,059	4,612	7,615	9,005
Segment Contribution	1,480	1,236	3,440	2,424
Corporate Segment [Member]
Non-Controlling Interest		4	(6)	22
Total Assets		5,334		5,334
Revenues
Segment Contribution	(4,899)	(5,401)	(9,948)	(11,324)
Interest, Financing and Miscellaneous Expense, Net	(49)	(24)	(142)	(137)
Tax Provision	$ (179)	$ (33)	$ (266)	$ (121)

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).

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