Guarantor Subsidiaries (Schedule Of Guarantor Subsidiaries, Balance Sheet) (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Cash and cash equivalents	$ 289,014	$ 457,024	$ 660,742	$ 708,151
Accounts receivable, net of allowance	1,242,075	1,395,248
Prepaid expenses	244,840	191,572
Other current assets	141,624	136,299
Total Current Assets	1,917,553	2,180,143
Structures, net	1,567,653	1,614,199
Other property, plant and equipment, net	1,018,137	1,084,865
Indefinite-lived intangibles - licenses	2,411,259	2,411,071
Indefinite-lived intangibles - permits	1,065,810	1,066,748
Other intangibles, net	1,141,481	1,206,727
Goodwill	4,170,632	4,187,424		4,202,187
Other assets	289,408	289,065
Total Assets	13,581,933	14,040,242	15,097,302
Accounts payable	132,419	132,258
Accrued expenses	718,418	799,475
Accrued interest	162,961	252,900
Deferred income	217,019	176,048
Other current liabilities	0	0
Current portion of long-term debt	2,844	3,604
Total Current Liabilities	1,233,661	1,364,285
Long-term debt	20,483,195	20,322,414
Deferred income taxes	1,566,965	1,563,888
Other long-term liabilities	451,795	454,863
Total Shareholders's Deficit	(10,153,683)	(9,665,208)
Total Liabilities and Shareholder's Deficit	$ 13,581,933	$ 14,040,242