Note 2 - Acquisition (Details Textual) - UEHC [Member] - USD ($) $ in Thousands		12 Months Ended
Dec. 13, 2021	Dec. 31, 2022	Dec. 31, 2021
Business Combination, Consideration Transferred, Total	$ 23,519
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles		$ 40
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Tax Liabilities		10
Goodwill, Purchase Accounting Adjustments		30
Operating Lease, Liability, Total	960
Operating Lease, Right-of-Use Asset	$ 960
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		28,145	$ 1,131
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual		320	128
Business Acquisition, Amortization Expense		726	30
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory		$ 55	121
Business Combination, Acquisition Related Costs			$ 354

The amount of amortization expense from business acquisition.

No definition available.

Name:	ulbi_BusinessAcquisitionAmortizationExpense
Namespace Prefix:	ulbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

No definition available.

+ Details

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Namespace Prefix:	ulbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
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+ Details

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

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-SubTopic 30
-Section 30
-Paragraph 8
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Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

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- Definition

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to inventory acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

+ Details

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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-Paragraph 1
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

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