When we impair goodwill we are crediting the goodwill and need to process the other side of the entry.
If we use the partial goodwill method then the goodwill impairment is removed from group retained earnings.
If we use the full goodwill method then the NCI share of the impairment is removed from the NCI and the group share is removed from the group retained earnings.
As these will be debit entries they will then reduce the group retained earnings and NCI.