Goodwill and Other Intangible Assets (Rollforwardl) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Balance as of December 31, 2011	$ 2,676,971	[1]
Additions	86,265
Effect of foreign currency translation	470
Balance as of September 30, 2012	2,763,706
Rental And Management [Member] | Domestic [Member]
Balance as of December 31, 2011	2,244,612	[1]
Additions	1,374
Effect of foreign currency translation	0
Balance as of September 30, 2012	2,245,986
Rental And Management [Member] | International [Member]
Balance as of December 31, 2011	430,359	[1]
Additions	84,891
Effect of foreign currency translation	470
Balance as of September 30, 2012	515,720
Network Development Services [Member]
Balance as of December 31, 2011	2,000	[1]
Additions	0
Effect of foreign currency translation	0
Balance as of September 30, 2012	$ 2,000

[1] Balances have been revised to reflect purchase accounting measurement period adjustments.