Basis of Presentation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Basis of Presentation [Line Items]
Cash and cash equivalents		$ 255,198	$ 259,067
Restricted cash		304	304
Operating lease liability		839
Right-of-use asset		831	988	$ 300
Subsequent Event [Member]
Basis of Presentation [Line Items]
Dividends Payable, Date Declared	Apr. 30, 2020
Dividends Payable, Amount Per Share	$ 5.50
Dividends, Cash	$ 170,500
Dividends Payable, Date to be Paid	May 28, 2020
Dividends Payable, Date of Record	May 14, 2020
Accounting Standards Update 2016-02 [Member] | Restatement Adjustment [Member]
Basis of Presentation [Line Items]
Operating lease liability				300
Right-of-use asset				$ 300
Telesat Canada [Member]
Basis of Presentation [Line Items]
Investments in affiliates, guarantee or other funding obligations		$ 0	$ 0