Investments in Affiliates (Equity in Net Income (Losses) of Affiliates) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Schedule of Equity Method Investments [Line Items]
Equity in net income (loss) of affiliates	$ 34,602	$ (117,074)
Telesat Canada [Member]
Schedule of Equity Method Investments [Line Items]
Equity in net income (loss) of affiliates	$ 34,602	$ (117,074)

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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