CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash Flows From Operating Activities:
Net income (loss)	$ 357,286	$ 385,321	$ 1,401,305	$ 390,075	$ 1,655,491	$ 2,165,407	$ 1,550,785	$ 1,550,785
Adjustments to reconcile net income (loss) to net cash flows from operating activities:
Depreciation and amortization					712,024	817,564	921,202
Impairment of long-lived assets						145,918
Realized and unrealized losses (gains) on investments					(11,908)	(99,997)	(119,092)
Non-cash, stock-based compensation					36,261	29,941	13,037
Deferred tax expense (benefit)					454,699	(485,973)	506,808
Change in long-term deferred revenue and other long-term liabilities					(3,303)	29,750	76,203
Other, net					(70,900)	(29,632)	9,573
Changes in current assets and current liabilities:
Trade accounts receivable					14,724	126,848	109,364
Allowance for doubtful accounts					(1,270)	(2,888)	(4,566)
Prepaid and accrued income taxes					93,618	(46,599)	(144,212)
Inventory					14,788	37,895	(43,157)
Other current assets					(46,772)	(63,154)	13,111
Trade accounts payable					(160,952)	(131,399)	33,976
Deferred revenue and other					(98,179)	(64,909)	(98,019)
Accrued programming and other accrued expenses					(70,480)	350,735	29,234
Net cash flows from operating activities					2,517,841	2,779,507	2,854,247
Cash Flows From Investing Activities:
Purchases of marketable investment securities					(1,403,890)	(566,373)	(345,210)
Sales and maturities of marketable investment securities					730,210	206,272	868,792
Settlement of derivative financial instruments							562,234
Purchases of property and equipment					(393,938)	(431,795)	(614,055)
Capitalized interest related to FCC authorizations (Note 2)					(922,759)	(953,498)	(724,329)
Purchases of FCC authorizations, including deposits (Note 14)						(4,711,154)	(1,500,000)
Purchases of strategic investments						(90,381)
Other, net					15,104	25,376	15,498
Net cash flows from investing activities					(1,975,273)	(6,521,553)	(1,737,070)
Cash Flows From Financing Activities:
Proceeds from issuance of senior notes							2,000,000
Proceeds from issuance of convertible notes						1,000,000	3,000,000
Purchases of convertible note hedges							(635,100)
Proceeds from issuance of warrants							375,600
Redemption and repurchases of senior notes					(1,108,489)	(1,074,139)	(1,500,000)
Repayment of long-term debt and capital lease obligations					(42,767)	(42,422)	(43,521)
Payments made to parent of transferred businesses						(7,098)	(34,446)
Net proceeds from Class A common stock options exercised and stock issued under the Employee Stock Purchase Plan					19,981	28,574	18,625
Debt issuance costs						(6,158)	(26,622)
Other, net					(3,270)	(1,994)	(606)
Net cash flows from financing activities					(1,134,545)	(103,237)	3,153,930
Net increase (decrease) in cash, cash equivalents, restricted cash and cash equivalents					(591,977)	(3,845,283)	4,271,107
Cash, cash equivalents, restricted cash and cash equivalents, beginning of period (Note 6)		$ 1,479,901		$ 5,325,184	1,479,901	5,325,184	1,054,077
Cash, cash equivalents, restricted cash and cash equivalents, end of period (Note 6)	$ 887,924		$ 1,479,901		$ 887,924	$ 1,479,901	$ 5,325,184	$ 1,054,077