XML 14 R55.htm IDEA: XBRL DOCUMENT v2.4.0.6
Income Taxes (Detail)
3 Months Ended 6 Months Ended
Jul. 31, 2012
Jul. 31, 2011
Jul. 31, 2012
Jul. 31, 2011
Effective Income Tax Rate Reconciliation, Tax Settlements 30.30% 47.50% 29.60% 38.70%