XML 70 R58.htm IDEA: XBRL DOCUMENT v3.25.3

Noncontrolling Interests - Summary Ownership of Viant Technology LLC (Details) - Viant Technology LLC - shares	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Minority Interest [Line Items]
Units Owned (shares)	62,403,160	63,122,293
Units Owned, Noncontrolling Interest (shares)	45,754,716	46,753,841
Ownership percentage by non-controlling interests	73.30%	74.10%
Ownership Percentage	100.00%	100.00%
Viant Technology Inc.
Minority Interest [Line Items]
Units Owned (shares)	16,648,444	16,368,452
Ownership percentage by Viant Technology Inc.	26.70%	25.90%

X

- Definition

Economic interests ownership percentage.

+ References

No definition available.

+ Details

Name:	dsp_EconomicInterestsOwnershipPercentage
Namespace Prefix:	dsp_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Number of units owned.

+ References

No definition available.

+ Details

Name:	dsp_NumberOfUnitsOwned
Namespace Prefix:	dsp_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of units owned.

+ References

No definition available.

+ Details

Name:	dsp_NumberOfUnitsOwnedNoncontrollingInterest
Namespace Prefix:	dsp_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Ownership interest percentage.

+ References

No definition available.

+ Details

Name:	dsp_OwnershipInterestPercentage
Namespace Prefix:	dsp_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

X

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

X

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

X

- Details

Name:	srt_OwnershipAxis=dsp_ViantTechnologyLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	dei_LegalEntityAxis=dsp_ViantTechnologyIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: