Income Taxes (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 6 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2012
Jun. 30, 2011
Jun. 30, 2011
Sep. 30, 2012
Dec. 31, 2011
Income Tax Disclosure [Abstract]          
Income tax expense (benefit) $ 1,180 $ 394 $ 2,739 $ 611  
Income tax benefit movement       (2,128)  
Income Tax Examination [Line Items]          
Unrecognized tax position as a result of a business acquisition         84
Foreign Tax Authority [Member]
         
Income Tax Examination [Line Items]          
Tax benefit from settlement of overseas tax filings for 2008, 2009 and 2010 $ 0