Income Taxes (Schedule Of Components Of Income Tax Expense (Benefit) For Continuing Operations) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Income Tax Disclosure [Abstract]
Document Fiscal Year Focus									2016
Federal, Current									$ 167,233	$ 245,473	$ 195,277
State, Current									(26,980)	31,501	33,274
Foreign, Current									8,735	9,788	6,749
Current income tax expense (benefit)									148,988	286,762	235,300
Federal, Deferred									19,937	(30,181)	28,624
State, Deferred									13,801	(4,040)	5,475
Foreign, Deferred									3,200	3,520	(2,380)
Deferred taxes									36,938	(30,701)	31,719
Total income taxes for continuing operations	$ 439,582	$ (67,851)	$ (95,201)	$ (90,604)	$ 465,926	$ (55,554)	$ (87,346)	$ (66,965)	$ 185,926	$ 256,061	$ 267,019