Wireless Service Provider Settlement Agreement (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	6 Months Ended	12 Months Ended
	Jul. 31, 2010	Jun. 30, 2010	Dec. 31, 2011
Wireless Service Provider Settlement Agreement [Abstract]
Wireless service provider agree to pay, amount	$ 141
Average residual revenue amounts, per quarter		9
Residual revenue			$ 0