LEGAL PROCEEDINGS (Details)	Jun. 30, 2025 Litigation Defendant
LEGAL PROCEEDINGS [Abstract]
Number of multi-district litigations \| Litigation	4
Number of groups of settling defendants \| Defendant	4

Refers to the number of groups of settling defendants.

No definition available.

Name:	artna_NumberOfGroupsOfSettlingDefendants
Namespace Prefix:	artna_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant