CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash Flows From Operating Activities:
Net income (loss)	$ 641,563	$ 99,274
Adjustments to reconcile net income (loss) to net cash flows from operating activities:
Depreciation and amortization	190,385	166,820
Impairment of long-lived assets (Note 2)		356,418
Realized and unrealized losses (gains) on investments and derivatives	6,283	(58)
Non-cash, stock-based compensation	19,375	16,418
Deferred tax expense (benefit)	147,285	28,942
Allowance for credit losses	(15,653)	21,450
Other, net	4,021	54,529
Changes in current assets and current liabilities, net	132,239	132,160
Net cash flows from operating activities	1,125,498	875,953
Cash Flows From Investing Activities:
Purchases of marketable investment securities	(139,692)	(432,172)
Sales and maturities of marketable investment securities	381,595	287,960
Purchases of property and equipment	(115,096)	(97,164)
Capitalized interest related to FCC authorizations (Note 2)	(281,721)	(241,825)
Refund of FCC authorization deposit (Note 11)	337,490
Other, net	2,006	2,065
Net cash flows from investing activities	184,582	(481,136)
Cash Flows From Financing Activities:
Repayment of long-term debt and finance lease obligations	(19,149)	(16,713)
Redemption and repurchases of senior notes	(205,354)
Early debt extinguishment	(2,517)
Net proceeds from Class A common stock options exercised and stock issued under the Employee Stock Purchase Plan	6,389	5,525
Other, net	(8,824)	2
Net cash flows from financing activities	(229,455)	(11,186)
Net increase (decrease) in cash, cash equivalents, restricted cash and cash equivalents	1,080,625	383,631
Cash, cash equivalents, restricted cash and cash equivalents, beginning of period (Note 6)	3,453,994	2,504,320
Cash, cash equivalents, restricted cash and cash equivalents, end of period (Note 6)	$ 4,534,619	$ 2,887,951