Employee Retirement Benefits (Tables)

9 Months Ended

Oct. 31, 2012

Employee Retirement Benefits [Abstract]

The components of net periodic benefit cost for postretirement benefits

The components of net periodic benefit cost for postretirement benefits are as follows:

	Three Months Ended				Nine Months Ended
	October 31, 2012		October 31, 2011		October 31, 2012		October 31, 2011
Service cost	$	46	$	30	$	140	$	90
Interest cost	84		83		252		251
Amortization of actuarial losses	59		32		175		95
Net periodic benefit cost	$	189	$	145	$	567	$	436