Amount of liability recognized arising from contingent consideration in a business combination.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
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Indicates valuation technique for measuring business combination contingent consideration liability.

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Fair Value Measurements - Summary of Qualitative Information About Level 3 Fair Value Measurements (Details) $ in Millions	Jun. 26, 2020 USD ($)	Jun. 28, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Contingent consideration		$ 1.4
Fair Value Level 3 [Member] \| EBITDA Multiple [Member]
Defined Benefit Plan Disclosure [Line Items]
Range	0.050
Fair Value Level 3 [Member] \| Discount Rate [Member]
Defined Benefit Plan Disclosure [Line Items]
Range	0.250
Fair Value Level 3 [Member] \| Rate on Return [Member]
Defined Benefit Plan Disclosure [Line Items]
Range	0.017
Fair Value Level 3 [Member] \| Salary Increase Rate [Member]
Defined Benefit Plan Disclosure [Line Items]
Range	0.045
Fair Value Level 3 [Member] \| Common Stock Purchase Obligation [Member]
Defined Benefit Plan Disclosure [Line Items]
Contingent consideration	$ 8.0
Business Combination Contingent Consideration Liability Valuation Technique Extensible List	us-gaap:ValuationTechniqueDiscountedCashFlowMember
Fair Value Level 3 [Member] \| Common Stock Purchase Obligation [Member] \| Revenue Multiple [Member]
Defined Benefit Plan Disclosure [Line Items]
Range	0.015
Fair Value Level 3 [Member] \| Pension Obligation [Member]
Defined Benefit Plan Disclosure [Line Items]
Contingent consideration	$ 3.7
Fair Value Level 3 [Member] \| Pension Obligation [Member]
Defined Benefit Plan Disclosure [Line Items]
Business Combination Contingent Consideration Liability Valuation Technique Extensible List	uctt:ValuationTechniqueProjectedUnitCreditMethodMember
Fair Value Level 3 [Member] \| Pension Obligation [Member] \| Discount Rate [Member]
Defined Benefit Plan Disclosure [Line Items]
Range	0.020