XML 58 R51.htm IDEA: XBRL DOCUMENT v2.4.0.6
Senior convertible notes (Details 1) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Summary of amortization of debt issuance expense        
Accretion of debt issuance costs $ 348 $ 329 $ 1,031 $ 973