Income Taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 31, 2017	[1]	Sep. 30, 2017	[1]	Jun. 30, 2017	[1]	Mar. 31, 2017	[1]	Dec. 31, 2016	[1]	Sep. 30, 2016	[1]	Jun. 30, 2016	[1]	Mar. 31, 2016	[1]	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal																	$ 13,422	$ 31,409	$ 41,002
State																	1,909	3,819	5,227
Foreign																	3,903	4,639	3,651
Total																	19,234	39,867	49,880
Deferred:
Federal																	5,582	(2,229)	(14,611)
State																	937	276	(1,147)
Foreign																	593	(797)	(348)
Total																	7,112	(2,750)	(16,106)
Total income tax provision	$ 6,705		$ 8,806		$ 8,722		$ 2,113		$ 6,814		$ 12,265		$ 6,448		$ 11,590		$ 26,346	$ 37,117	$ 33,774

[1] Fluctuations in our effective income tax rate between quarters generally relates to the accounting for discrete income tax items in any given quarter, and revisions of estimates for certain income tax components during the year. For 2017: Our effective income tax rates for the first, second, third, and fourth quarters were 9%, 43%, 38%, and 31%, respectively. The first quarter 2017 effective income tax rate reflects an approximately $5 million net benefit resulting from Comcast’s exercise of 1.4 million vested stock warrants in January 2017 (see Note 10) and the fourth quarter effective income tax rate includes a $2 million benefit from the remeasurement of U.S.-based net deferred tax liabilities as required under the U.S. Tax reform enacted in December 2017 (see Note 7). For 2016: Our effective income tax rates for the first, second, third, and fourth quarters were 35%, 37%, 41%, and 35%, respectively.