Employee Benefit And Retirement Plans (Reconciliation Of Benefit Obligations, Plan Assets, And Funded Status) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Employee Benefit And Retirement Plans [Abstract]
Projected benefit obligation at beginning of year	$ 149,429	$ 136,264
Interest cost	6,203	6,261	6,533
Acturial (gains) and losses	(7,615)	10,801
Benefits paid	(3,875)	(3,897)
Projected benefit obligation at end of year	144,142	149,429	136,264
Fair value of plan assets at beginning of year	95,733	85,717
Actual return on plan assets	8,483	8,993
Company contributions	2,258	4,920
Fair value of plan assets at end of year	102,599	95,733	85,717
Funded status of the plan	(41,543)	(53,696)
Unrecognized net actuarial loss	42,589	52,703
Prepaid (accrued) benefit cost	1,046	(993)
Defined benefit pension liabilities	(41,543)	(53,696)
Accumulated other comprehensive loss	42,589	52,703
Net amount recoognized	$ 1,046	$ (993)