Business combination held back amount.

No definition available.

Name:	dzsi_BusinessCombinationHeldBackAmount
Namespace Prefix:	dzsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Business combination held back amounts released.

+ References

No definition available.

+ Details

Name:	dzsi_BusinessCombinationHeldBackAmountsReleased
Namespace Prefix:	dzsi_
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_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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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+ Details

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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 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

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+ Details

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

- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

+ Details

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Details

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Balance Type:
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- Details

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Namespace Prefix:
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Period Type:

- Details

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Balance Type:
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- Details

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Namespace Prefix:
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Balance Type:
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Business Combinations - Additional Information (Details) - USD ($) $ in Thousands			1 Months Ended	3 Months Ended
	Mar. 03, 2021	Feb. 05, 2021	Apr. 30, 2021	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Business Acquisition [Line Items]
Goodwill		$ 1,948		$ 6,145	$ 3,977	$ 3,977
Tangible assets, net		718
Developed technologies		3,160
Optelian Access Networks Corporation
Business Acquisition [Line Items]
Purchase price		7,490
Measurement period adjustment of intangible assets				$ 500
Goodwill		1,900
Optelian Access Networks Corporation \| Optelian Products
Business Acquisition [Line Items]
Purchase price		1,900
Held back amount		$ 300
RIFT Inc
Business Acquisition [Line Items]
Purchase price	$ 500
Goodwill	200
Held back amount released			$ 200
Tangible assets, net	100
RIFT Inc \| Developed Technology
Business Acquisition [Line Items]
Developed technologies	$ 200