Contract Balances (Tables)

12 Months Ended

Dec. 31, 2020

Contract Balances

Summary of activity in the allowance for doubtful accounts

Allowance for credit losses	Balance at Beginning of Year		Current Period Provision for Expected Credit Losses		Write-offs Charged Against Allowance		Balance at End of Year
	(In thousands)
For the years ended:
December 31, 2020	$	19,280	$	84,697	$	(31,699)	$	72,278
December 31, 2019	$	16,966	$	69,866	$	(67,552)	$	19,280
December 31, 2018	$	15,511	$	98,575	$	(97,120)	$	16,966

Schedule of changes in deferred revenue related to contracts with subscribers

	Contract
	Liabilities
	(In thousands)
Balance as of December 31, 2019	$	613,272
Recognition of unearned revenue		(9,622,625)
Deferral of revenue		9,788,185
Balance as of December 31, 2020	$	778,832