Quarterly report pursuant to Section 13 or 15(d)

Income taxes (Details)

v2.4.0.8
Income taxes (Details)
3 Months Ended 6 Months Ended
Jan. 31, 2014
Jan. 31, 2013
Jan. 31, 2014
Jan. 31, 2013
Income Tax Disclosure [Abstract]        
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent 0.10% 3.10% (0.90%) 2.50%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent     34.00%