Quarterly report pursuant to Section 13 or 15(d)

Derivative Contracts (Details Textual)

v2.4.0.8
Derivative Contracts (Details Textual)
Jun. 30, 2013
Jan. 30, 2013
Dec. 31, 2012
Derivative Contracts (Textual) [Abstract]      
Convertible senior notes interest rate 3.00% 3.00% 3.00%