Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Taxes [Line Items]
Income Taxes Receivable	$ 15,654		$ 29,313
Accounts payable and accrued liabilities	$ 506,638		$ 520,236
Effective Income Tax Rate	22.60%	29.60%
Income Tax Benefit,, Adjustment of Deferred Tax	$ 15,700
CableONE [Member]
Income Taxes [Line Items]
Income Taxes Receivable	15,900
Accounts payable and accrued liabilities	$ 15,900