XML 48 R5.htm IDEA: XBRL DOCUMENT v2.4.0.6
Consolidated Statements of Income and Comprehensive Income Parenthetical (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Apr. 30, 2012
Apr. 30, 2011
Consolidated Statements of Income [Abstract]    
Income taxes on postretirement benefits $ 20 $ 15