Concentration Of Credit Risk (Summary Of Significant Customers And The Percentage Of Total Revenue For The Specified Time Periods Derived From Such Customers) (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
AT&T [Member] | Site Total Revenue [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	23.80%	23.90%	23.80%
AT&T [Member] | Site Leasing [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	26.80%	28.00%	27.70%
Sprint [Member] | Site Total Revenue [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	19.80%	20.40%	21.90%
Sprint [Member] | Site Leasing [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	22.30%	23.60%	25.30%
Verizon Wireless [Member] | Site Total Revenue [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	14.80%	14.80%	15.40%
Verizon Wireless [Member] | Site Leasing [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	15.50%	15.40%	16.00%
Verizon Wireless [Member] | Site Development Consulting [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	17.50%	15.10%	23.60%
Verizon Wireless [Member] | Site Development Construction [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	7.30%	10.20%	8.30%
T-Mobile [Member] | Site Total Revenue [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	10.70%	11.60%	13.70%
T-Mobile [Member] | Site Leasing [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	11.20%	11.70%	11.80%
T-Mobile [Member] | Site Development Consulting [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	8.50%	6.00%	13.90%
T-Mobile [Member] | Site Development Construction [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	6.60%	11.80%	28.20%
Ericsson, Inc. [Member] | Site Development Construction [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	10.10%	3.00%	0.30%
Nsoro Mastec, LLC [Member] | Site Development Consulting [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	9.10%	13.40%	9.30%
Nsoro Mastec, LLC [Member] | Site Development Construction [Member]
Concentration Risk [Line Items]
Concentration risk percentage of revenue	42.70%	36.00%	24.90%