Goodwill And Intangible Assets (Schedule Of Intangible Assets) (Details) - USD ($) $ in Thousands	Oct. 31, 2015	Apr. 30, 2015	Oct. 31, 2014
Goodwill and Intangible Assets [Line Items]
Gross Carrying Amount	$ 756,749	$ 688,894	$ 639,567
Accumulated Amortization	(290,525)	(256,752)	(225,522)
Net	466,224	432,142	414,045
Tax Services [Member] | Reacquired Franchise Rights [Member]
Goodwill and Intangible Assets [Line Items]
Gross Carrying Amount	316,142	294,647	278,159
Accumulated Amortization	(56,731)	(46,180)	(33,721)
Net	259,411	248,467	244,438
Tax Services [Member] | Customer Relationships [Member]
Goodwill and Intangible Assets [Line Items]
Gross Carrying Amount	182,137	170,851	148,407
Accumulated Amortization	(89,340)	(78,157)	(66,714)
Net	92,797	92,694	81,693
Tax Services [Member] | Software and Software Development Costs [Member]
Goodwill and Intangible Assets [Line Items]
Gross Carrying Amount	123,263	118,865	110,140
Accumulated Amortization	(88,091)	(80,689)	(77,925)
Net	35,172	38,176	32,215
Tax Services [Member] | Noncompete Agreements [Member]
Goodwill and Intangible Assets [Line Items]
Gross Carrying Amount	32,428	30,630	28,960
Accumulated Amortization	(24,632)	(23,666)	(22,774)
Net	7,796	6,964	6,186
Tax Services [Member] | Franchise Agreements
Goodwill and Intangible Assets [Line Items]
Gross Carrying Amount	19,201	19,201	19,201
Accumulated Amortization	(8,854)	(8,214)	(7,574)
Net	10,347	10,987	11,627
Tax Services [Member] | Purchased Technology
Goodwill and Intangible Assets [Line Items]
Gross Carrying Amount	54,700	54,700	54,700
Accumulated Amortization	(22,877)	(19,846)	(16,814)
Net	31,823	$ 34,854	$ 37,886
Tax Services [Member] | Other Intangible Assets [Member]
Goodwill and Intangible Assets [Line Items]
Gross Carrying Amount	28,878
Accumulated Amortization	0
Net	$ 28,878