Investments in Unconsolidated Entities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Equity and cost method investments
Investments in unconsolidated entities	$ 165,529		$ 144,531
Equity in earnings of unconsolidated entities	26,835	21,614
Equity method investments, combined income statements
Revenues	1,492,726	1,431,372
Operating expenses	1,066,967	1,071,887
Operating income	425,759	359,485
Other income, net	588	916
Net income	426,347	360,401
Los Angeles SMSA Limited Partnership
Equity and cost method investments
Equity in earnings of unconsolidated entities	$ 20,600	$ 17,100
Ownership interest in equity method investment	5.50%	5.50%