v3.26.1
Basis of Presentation (Details)
6 Months Ended
Jun. 30, 2026
business_unit
Basis of Presentation [Abstract]
Number of business units
1
X
- References
No definition available.
+ Details
Name:
gmab_BasisOfPresentationAbstract
Namespace Prefix:
gmab_
Data Type:
xbrli:stringItemType
Balance Type:
na
Period Type:
duration
X
- Definition
Number Of Business Units
+ References
No definition available.
+ Details
Name:
gmab_NumberOfBusinessUnits
Namespace Prefix:
gmab_
Data Type:
xbrli:integerItemType
Balance Type:
na
Period Type:
duration