Derivatives - Foreign Currency Exchange Contracts (Details) - Not Designated as Hedging Instrument $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2019 USD ($) ¥ / $ $ / €	Dec. 31, 2018 USD ($) ¥ / $ $ / € $ / R$
USD/Brazilian Real
Derivative [Line Items]
Notional value	$ 2,000	$ 1,000
Forward rate	3.8677	3.8651
Unrealized gain/(loss) recorded at balance sheet date	$ (19)	$ 5
USD/Euro
Derivative [Line Items]
Notional value	$ 29,000	$ 20,000
Forward rate	1.1394	1.1421
Unrealized gain/(loss) recorded at balance sheet date	$ (17)	$ (97)
USD/Chinese Yuan Renminbi \| USD/Chinese Yuan Renminbi
Derivative [Line Items]
Notional value		$ 27,000
Forward rate \| ¥ / $		6.8969
Unrealized gain/(loss) recorded at balance sheet date		$ (116)
USD/Chinese Yuan Renminbi \| USD/Chinese Yuan Renminbi
Derivative [Line Items]
Notional value		$ 5,000
Forward rate \| ¥ / $		6.9245
Unrealized gain/(loss) recorded at balance sheet date		$ (41)

Contractual rate at which a foreign currency can be purchased or sold.

No definition available.

Name:	us-gaap_DerivativeForwardExchangeRate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

+ Details

Name:	us-gaap_DerivativeNotionalAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_HedgingDesignationAxis=us-gaap_NondesignatedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=currency_BRL
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=currency_EUR
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=currency_CNY
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=ueic_ForeignExchangeForwardUSDChineseYuanRenminbiContract1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=ueic_ForeignExchangeForwardUSDChineseYuanRenminbiContract2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: