Selling Arrangement (Details) (USD $)	1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 28, 2011	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Selling Arrangement
Payment for arrangement to sell signs				$ 542,000
Selling Agreement
Selling Arrangement
Payment for arrangement to sell signs	4,000,000
Term of arrangement	10 years
Amortization expense		100,000	100,000	200,000	200,000
2014		400,000		400,000
2015		400,000		400,000
2016		400,000		400,000
2017		400,000		400,000
2018		$ 400,000		$ 400,000