Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Dec. 31, 2021
Entity Registrant Name	HEARTLAND GROUP, INC.
Entity Central Index Key	0000809586
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	Apr. 28, 2022
Document Effective Date	May 01, 2022
Prospectus Date	May 01, 2022
HEARTLAND MID CAP VALUE FUND \| Institutional Class
Prospectus:
Trading Symbol	HNMDX
HEARTLAND MID CAP VALUE FUND \| Investor Class
Prospectus:
Trading Symbol	HRMDX
HEARTLAND VALUE PLUS FUND \| Investor Class
Prospectus:
Trading Symbol	HRVIX
HEARTLAND VALUE PLUS FUND \| Institutional Class
Prospectus:
Trading Symbol	HNVIX
HEARTLAND VALUE FUND \| Investor Class
Prospectus:
Trading Symbol	HRTVX
HEARTLAND VALUE FUND \| Institutional Class
Prospectus:
Trading Symbol	HNTVX

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