Supplemental Cash Flow Information - Schedule of Non-Cash Investing Activities (Details) - CAD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Schedule of Non-Cash Investing Activities [Abstract]
Satellites, property and other equipment	$ 35,691	$ 73,407

The amount of non-cash activities related to satellites, property and other equipment.

No definition available.

Name:	tsat_NoncashActivitiesRelatedToSatellitesPropertyAndOtherEquipment
Namespace Prefix:	tsat_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration