Concentration Of Credit Risk

12 Months Ended

Dec. 31, 2011

Concentration Of Credit Risk [Abstract]

Concentration Of Credit Risk

11. CONCENTRATION OF CREDIT RISK

The Company's credit risks consist primarily of accounts receivable with national, regional and local wireless service providers and federal and state government agencies. The Company performs periodic credit evaluations of its customers' financial condition and provides allowances for doubtful accounts, as required, based upon factors surrounding the credit risk of specific customers, historical trends and other information. The Company generally does not require collateral. The following is a list of significant customers (representing at least 10% of revenue for all periods reported) and the percentage of total revenue for the specified time periods derived from such customers:

	Percentage of Total Revenues   For the year ended December 31,
	2011			2010			2009
AT&T		23.8	%		23.9	%		23.8	%
Sprint		19.8	%		20.4	%		21.9	%
Verizon Wireless		14.8	%		14.8	%		15.4	%
T-Mobile		10.7	%		11.6	%		13.7	%

The Company's site leasing, site development consulting and site development construction segments derive revenue from these customers. Client percentages of total revenue in each of the segments are as follows:

		00.00			00.00			00.00
	Percentage of Site Leasing Revenues For the year ended December 31,
	2011			2010			2009
AT&T		26.8	%		28.0	%		27.7	%
Sprint		22.3	%		23.6	%		25.3	%
Verizon Wireless		15.5	%		15.4	%		16.0	%
T-Mobile		11.2	%		11.7	%		11.8	%

		00.00			00.00			00.00
	Percentage of Site Development Consulting Revenues   For the year ended December 31,
	2011			2010			2009
Verizon Wireless		17.5	%		15.1	%		23.6	%
Nsoro Mastec, LLC		9.1	%		13.4	%		9.3	%
T-Mobile		8.5	%		6.0	%		13.9	%

	Percentage of Site Development Construction Revenues For the year ended December 31,
	2011			2010			2009
Nsoro Mastec, LLC		42.7	%		36.0	%		24.9	%
Ericsson, Inc.		10.1	%		3.0	%		0.3	%
Verizon Wireless		7.3	%		10.2	%		8.3	%
T-Mobile		6.6	%		11.8	%		28.2	%

Five significant customers comprised 50.4% of total gross accounts receivable at December 31, 2011 compared to five significant customers which comprised 50.5% of total gross accounts receivable at December 31, 2010.