Concentrations of Credit Risk (Tables)

6 Months Ended

Jun. 30, 2014

Concentrations of Credit Risk [Abstract]

Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]

Major Customers

The following table summarizes the percentage of the consolidated revenues for those customers accounting for more than 10% of the consolidated revenues (all of such customer revenues relate to our CCUSA segment). The following table is after giving effect to AT&T's acquisition of Leap Wireless (completed in March 2014).

	Six Months Ended June 30,
	2014		2013
Sprint	26	%	30	%
AT&T	26	%	20	%
T-Mobile	21	%	21	%
Verizon Wireless	16	%	16	%
Total	89	%	87	%