Description of the Business (Notes)	12 Months Ended
Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of the Business [Text Block]	Description of the Business ManTech International Corporation (depending on the circumstances, “ManTech” “Company” “we” “our” “ours” or “us”) provides mission-focused technology solutions and services for U.S. defense, intelligence community and federal civilian agencies. We excel in full-spectrum cyber, secure mission & enterprise IT, advanced data analytics, software and systems development, intelligent systems engineering, intelligence mission support and mission operations.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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