Stockholders' Equity - Activities Under Equity Plan (Detail)	3 Months Ended												39 Months Ended		19 Months Ended	12 Months Ended	19 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Dec. 31, 2013	May 16, 2012	Dec. 31, 2013 Short-Term Incentive Plan (STIP) [Member]	Dec. 31, 2013 Restricted Stock Units [Member] 2011 Long Term Incentive Plan [Member]	Dec. 31, 2013 Restricted Stock Units [Member] 2011 Long Term Incentive Plan [Member]	Dec. 31, 2013 Wireless Operations [Member] Restricted Stock Units [Member] 2011 Long Term Incentive Plan [Member]	Dec. 31, 2013 Software Operations [Member] Restricted Stock Units [Member] 2011 Long Term Incentive Plan [Member]	Dec. 31, 2013 Non Executive Directors [Member] Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Equity securities available														2,194,986
Forfeited, shares																50,750	152,044			3,189
Granted, shares	(6,266)	(4,606)	(4,712)	(5,350)	(5,263)	(4,084)	(3,769)	(3,785)	(3,979)	(3,439)	(3,627)	(2,955)	(51,835)		(41,702)	(434,811)		(392,719)	(164,765)	(30,281)
Ending Balance, Equity securities available													1,720,752	2,194,986