Performance-Based Common Stock Warrants - Assumptions Used in Valuation and Weighted Average Fair Value of Warrants (Details) - Common Stock Purchase Warrants	Sep. 30, 2019 $ / shares	Sep. 30, 2018 $ / shares
Class of Warrant or Right [Line Items]
Fair value (in dollars per share)	$ 16.78	$ 10.06
Price of Universal Electronics Inc. common stock (in dollars per share)	$ 51.09	$ 38.95
Risk-free interest rate
Class of Warrant or Right [Line Items]
Valuation assumption rate	0.0156	0.0292
Expected volatility
Class of Warrant or Right [Line Items]
Valuation assumption rate	0.4782	0.4100
Expected life
Class of Warrant or Right [Line Items]
Expected life	3 years 3 months	4 years 3 months

Class of Warrant or Right, Fair Value

No definition available.

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- 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

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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- Definition

Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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