Employee Retirement Benefits (Tables)

6 Months Ended

Jul. 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				Six Months Ended
	July 31, 2012		July 31, 2011		July 31, 2012		July 31, 2011
Service cost	$	47	$	30	$	94	$	60
Interest cost	84		84		168		168
Amortization of actuarial losses	58		31		116		63
Net periodic benefit cost	$	189	$	145	$	378	$	291