The amount of outstanding funds that the entity is obligated to repay.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The interest rate on borrowings. [Refer: Borrowings]

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The cash outflow for debt issue costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 17
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Borrowings maturity date, description.

+ References

No definition available.

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- Definition

The amount of exposure to loss resulting from credit risk.

+ References

No definition available.

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- Definition

Represents the amount of debt exchange.

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No definition available.

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No definition available.

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Open-market operation, any of the purchases and sales of government securities and sometimes commercial paper by the central banking authority for the purpose of regulating the money supply and credit conditions on a continuous basis.

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No definition available.

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Percentage of repurchase of principal amount.

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No definition available.

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Represent the amount of repurchased principal amount.

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No definition available.

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- Definition

The value of revolving credit facility.

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No definition available.

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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No definition available.

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Indebtedness (Details) $ in Thousands, $ in Millions					3 Months Ended			6 Months Ended
Indebtedness (Details) $ in Thousands, $ in Millions	Sep. 13, 2024 CAD ($)	Apr. 27, 2021 USD ($)	Dec. 06, 2019 CAD ($)	Oct. 11, 2019 USD ($)	Jun. 30, 2026 CAD ($)	Jun. 30, 2025 CAD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 CAD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 CAD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 CAD ($)	Sep. 30, 2025	Dec. 31, 2024	Dec. 06, 2019 USD ($)
Indebtedness [Line Items]
Senior unsecured notes issued (in Dollars)					$ 3,794,167			$ 3,794,167				$ 3,493,607
Loan interest rate					5.00%			5.00%
Repurchased principal amount (in Dollars)	$ 2,140,000
Open market purchases	$ 400,000
Interest expense on borrowings					65,802	57,453		$ 127,270		113,905
Warrants and rights outstanding terms								10 years	10 years
Government of Quebec [Member]
Indebtedness [Line Items]
Payments for debt issue costs					15,700			$ 36,200
Interest expense on borrowings								54,400
Government of Canada [Member]
Indebtedness [Line Items]
Payments for debt issue costs					84,300			193,800
Senior Secured Credit Facilities [Member]
Indebtedness [Line Items]
Revolving credit facility (in Dollars)			$ 200,000
Term Loan B — U.S. Facility [Member]
Indebtedness [Line Items]
Credit exposure (in Dollars)															$ 1,908.5
Telesat Lightspeed Financing Warrants [Member]
Indebtedness [Line Items]
Loan interest rate														11.87%
Telesat Lightspeed Financing [Member]
Indebtedness [Line Items]
Loan interest rate													11.87%
2027 Senior Unsecured Notes [Member]
Indebtedness [Line Items]
Repurchased principal amount (in Dollars)						11,400	$ 8.2			11,400	$ 8.2
Debt Exchange						4,500	$ 3.3	4,500	$ 3.3
2027 Senior Unsecured Notes [Member] \| 6.5% Senior Notes [Member]
Indebtedness [Line Items]
Borrowings maturity date, description				October 2027
2027 Senior Unsecured Notes [Member] \| Private Placements [Member]
Indebtedness [Line Items]
Senior unsecured notes issued (in Dollars)				$ 550.0
Loan interest rate				6.50%
2026 Senior Secured Notes [Member]
Indebtedness [Line Items]
Repurchased principal amount (in Dollars)		$ 500.0
Repurchase of Principal Amount		5.625%
2027 Senior Secured Notes [Member]
Indebtedness [Line Items]
Borrowings maturity date, description			June 2027
Repurchased principal amount (in Dollars)
2027 Senior Secured Notes [Member] \| Private Placements [Member]
Indebtedness [Line Items]
Senior unsecured notes issued (in Dollars)															$ 400.0
Loan interest rate			4.875%												4.875%