Operating Segments and Concentrations of Credit Risk

12 Months Ended

Dec. 31, 2015

Operating Segments and Concentrations of Credit Risk [Abstract]

Operating Segments and Concentrations of Credit Risks

Operating Segments and Concentrations of Credit Risk

Operating Segments

The Company has determined that presently, following the sale of CCAL, it has one reportable operating segment consisting of its U.S. operations, which is consistent with its current operational and financial reporting structure. Financial results for the Company are currently reported to the Company's management team and board of directors in this manner.

Prior to its sale in May 2015, CCAL, the Company's previously 77.6% owned subsidiary that owned and operated towers in Australia, was a reportable segment. As a result of the sale of CCAL, the Company's segment data has been reclassified for all periods presented to include CCAL on a discontinued operations basis.

The Company will continue its evaluation of its operating segments following the disposition of CCAL and its change in strategic focus to its U.S. business. To the extent the Company makes changes to its financial reporting or organizational structure, including the integration of the Sunesys Acquisition, the Company will evaluate any impact such changes may have to its segment reporting.

Major Customers

The following table summarizes the percentage of the consolidated revenues for those customers accounting for more than 10% of the consolidated revenues.

	Years Ended December 31,
	2015		2014		2013
AT&T (a)	27	%	26	%	23	%
T-Mobile (a)	22	%	21	%	24	%
Verizon Wireless	21	%	18	%	17	%
Sprint (a)	19	%	25	%	28	%
Total	89	%	90	%	92	%

(a) All periods presented are after giving effect to recent customer consolidation activity, including T-Mobile's acquisition of MetroPCS (completed in April 2013), Sprint's acquisition of Clearwire (completed in July 2013), and AT&T's acquisition of Leap Wireless (completed in March 2014). 

Concentrations of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk are primarily cash and cash equivalents, restricted cash and trade receivables. The Company mitigates its risk with respect to cash and cash equivalents by maintaining such deposits at high credit quality financial institutions and monitoring the credit ratings of those institutions. The Company's restricted cash is predominately held and directed by a trustee (see note 2).

The Company derives the largest portion of its revenues from customers in the wireless industry. The Company also has a concentration in its volume of business with AT&T, T-Mobile, Verizon Wireless, and Sprint or their agents that accounts for a significant portion of the Company's revenues, receivables, and deferred site rental receivables. The Company mitigates its concentrations of credit risk with respect to trade receivables by actively monitoring the creditworthiness of its tenants, the use of tenant leases with contractually determinable payment terms, or proactive management of past due balances.