Investments - Equity Method Investments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended				3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 30, 2014 Again Faster	Jun. 30, 2013 Again Faster	Jun. 30, 2014 Again Faster	Jun. 30, 2013 Again Faster	Dec. 31, 2013 Again Faster	Jun. 30, 2014 iGo	Jun. 30, 2013 iGo	Jun. 30, 2014 iGo	Jun. 30, 2013 iGo	Dec. 31, 2013 iGo	Aug. 31, 2013 iGo	Jun. 30, 2014 API	Jun. 30, 2013 API	Jun. 30, 2014 API	May 31, 2014 API
Schedule of Equity Method Investments [Line Items]
Ownership						40.00%		40.00%		40.00%	44.70%		44.70%		44.70%	44.70%	20.60%		20.60%	20.50%
Value of investment											$ 4,200		$ 4,200				$ 31,330		$ 31,330
Carrying Value	37,571		37,571		8,339	3,378		3,378		3,671	2,863		2,863		4,668
Income (Loss) Recognized	$ 2,874	$ 0	$ 1,441	$ 0		$ (164)	$ 0	$ (293)	$ 0		$ (501)	$ 0	$ (1,805)	$ 0			$ 3,539	$ 0	$ 3,539