Consolidated Balance Sheets Balance Sheet Parenthetical (USD $)
In Thousands, except Share data, unless otherwise specified
Sep. 30, 2014
Dec. 31, 2013
Allowance for doubtful accounts $ 750 $ 805
Preferred stock, par value $ 0.0001 $ 0.0001
Preferred stock, shares authorized 10,000,000 10,000,000
Preferred stock, shares issued 0 0
Preferred stock, shares outstanding 0 0
Common Class B [Member]
   
Par value of authorized shares (USD per share) $ 0.0001 $ 0.0001
Shares authorized for issuance 75,000,000 75,000,000
Shares issued and outstanding 24,691,681 33,421,033
Common stock, shares outstanding 24,691,681 33,421,033
Common Class A [Member]
   
Par value of authorized shares (USD per share) $ 0.0001 $ 0.0001
Shares authorized for issuance 750,000,000 750,000,000
Shares issued and outstanding 44,631,686 28,777,653
Common stock, shares outstanding 44,631,486 28,777,653