Basis of Presentation and Consolidation and Summary of Significant Accounting Policies - Income Taxes (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023
Income Tax Contingency [Line Items]
Valuation allowance	$ 460	$ 460	$ 7,709	$ 460
Common Class A \| Direct Digital Management LLC
Income Tax Contingency [Line Items]
Number of units exchanged (in shares)	7,455	7,455	0	7,455

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant