CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash Flows From Operating Activities:
Net income (loss)	$ 390,075	$ 411,944
Adjustments to reconcile net income (loss) to net cash flows from operating activities:
Depreciation and amortization	204,630	227,566
Realized and unrealized losses (gains) on investments	(2,272)	(66,980)
Non-cash, stock-based compensation	6,774	4,477
Deferred tax expense (benefit)	150,006	78,730
Other, net	6,752	9,002
Changes in current assets and current liabilities, net	180,802	263,297
Net cash flows from operating activities	936,767	928,036
Cash Flows From Investing Activities:
Purchases of marketable investment securities	(58,876)	(23,059)
Sales and maturities of marketable investment securities	78,703	440,669
Settlement of derivative financial instruments		220,871
Purchases of property and equipment	(114,899)	(161,200)
Capitalized interest related to FCC authorizations (Note 2)	(282,597)	(225,360)
Other, net	(85,305)	13,630
Net cash flows from investing activities	(462,974)	265,551
Cash Flows From Financing Activities:
Proceeds from issuance of convertible notes (Note 9)	1,000,000
Redemption and repurchases of senior notes		(1,500,000)
Repayment of long-term debt and capital lease obligations	(9,162)	(10,348)
Payments made to parent of transferred businesses	(7,098)	(30,525)
Net proceeds from Class A common stock options exercised and stock issued under the Employee Stock Purchase Plan	6,374	3,056
Debt issuance costs	(6,158)
Other, net		103
Net cash flows from financing activities	983,956	(1,537,714)
Net increase (decrease) in cash and cash equivalents	1,457,749	(344,127)
Cash and cash equivalents, beginning of period	5,324,503	1,053,983
Cash and cash equivalents, end of period	$ 6,782,252	$ 709,856