Employee Benefit Plans (Tables)

9 Months Ended

Dec. 31, 2012

Compensation and Retirement Disclosure [Abstract]

Components of net postretirement medical expense

The components of net postretirement medical expense for the Officer Medical Plan were as follows:

	Three Months Ended December 31,				Nine Months Ended December 31,
	2012		2011		2012		2011
Service cost	$	973	$	978	$	2,919	$	2,934
Interest cost	787		747		2,360		2,240
Total postretirement medical expense	$	1,760	$	1,725	$	5,279	$	5,174