Derivative Financial Instruments - Summary of Information Related to Number of and Notional Amount of Interest Rate Related Derivative Instruments (Details) - Designated as Hedging Instrument	Mar. 31, 2019 USD ($) DerivativeInstrument	Dec. 31, 2018 USD ($) DerivativeInstrument
Interest Rate Swaps and Collars
Derivative [Line Items]
Number of Instruments \| DerivativeInstrument	12	12
Notional Amount \| $	$ 210,000,000	$ 210,000,000
Cross Currency Swaps \| GBP
Derivative [Line Items]
Number of Instruments \| DerivativeInstrument	1
Notional Amount \| $	$ 112,753,000
Cross Currency Swaps \| EUR
Derivative [Line Items]
Number of Instruments \| DerivativeInstrument	1
Notional Amount \| $	$ 21,060,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

Name:	invest_DerivativeNotionalAmount
Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- 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

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=diod_InterestRateSwapsAndCollarsMember
Namespace Prefix:
Data Type:	na
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- Details

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

- Details

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

- Details

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