Commitments And Contingencies (Narrative) (Details) (USD $)	1 Months Ended	9 Months Ended
	Dec. 31, 2000 towers	Sep. 30, 2013
AT&T Transaction [Member]
Long-term Purchase Commitment [Line Items]
Number of towers leased or subleased		2,450
Lessee leasing arrangements, operating leases, term of contract		27 years
Aggregate purchase option price for towers		$ 585,300,000
Purchase price accretion rate (per year)		10.00%
Right to continue to lease space, number of terms		4
Lessee leasing arrangements, operating leases, renewal term		5 years
ALLTEL Transaction [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase option price for towers		70,700,000
Purchase price accretion rate (per year)		3.00%
Long-term purchase commitment, time period	P15Y
Capital leased assets, number of units	1,800
Cash purchase price per tower	27,500
Purchase price of tower in shares of common stock		769
Value of potential shares payable		$ 101,200,000