Condensed Consolidating Financial Statements (Income Statement) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Total revenues	$ 451,882	$ 474,543	$ 708,399	$ 740,676
Cost of revenues	388,777	392,513	825,565	832,422
Selling, general and administrative	187,897	201,872	400,372	435,911
Total operating expenses	576,674	594,385	1,225,937	1,268,333
Other income, net	(170)	3,055	4,978	13,993
Interest expense on borrowings	(25,940)	(23,573)	(70,026)	(46,329)
Other income, net	304	(6,140)	(30)	(11,335)
Loss from continuing operations before income tax benefit	(150,598)	(146,500)	(582,616)	(571,328)
Income tax benefit	(49,386)	(67,851)	(216,963)	(253,656)
Net loss from continuing operations	(101,212)	(78,649)	(365,653)	(317,672)
Net income (loss) from discontinued operations	(3,302)	(3,080)	(8,754)	(8,723)
Net loss	(104,514)	(81,729)	(374,407)	(326,395)
Other comprehensive income (loss)	1,759	(4,641)	(4,130)	(22,589)
Comprehensive loss	(102,755)	(86,370)	(378,537)	(348,984)
Block Financial Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Total revenues	53,990	52,500	80,428	91,239
Cost of revenues	33,242	37,557	47,514	59,122
Selling, general and administrative	10,693	1,097	14,905	18,847
Total operating expenses	43,935	38,654	62,419	77,969
Other income, net	12,237	6,343	18,172	17,878
Interest expense on borrowings	(25,858)	(23,467)	(69,420)	(45,988)
Other income, net	2,741	(3,212)	(1,161)	(3,956)
Loss from continuing operations before income tax benefit	(825)	(6,490)	(34,400)	(18,796)
Income tax benefit	(2,939)	(25,161)	(14,695)	(25,922)
Net loss from continuing operations	2,114	18,671	(19,705)	7,126
Net income (loss) from discontinued operations	(3,282)	(3,078)	(8,733)	(8,721)
Net loss	(1,168)	15,593	(28,438)	(1,595)
Other comprehensive income (loss)				(8,444)
Comprehensive loss	(1,168)	15,593	(28,438)	(10,039)
Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total revenues	411,099	423,610	641,322	651,125
Cost of revenues	364,286	356,521	786,946	774,985
Selling, general and administrative	181,660	200,657	389,923	413,532
Total operating expenses	545,946	557,178	1,176,869	1,188,517
Other income, net	12,194	3,278	18,517	4,734
Interest expense on borrowings	(82)	(106)	(606)	(341)
Other income, net	(13,971)	8,482	(43,118)	(16,939)
Loss from continuing operations before income tax benefit	(136,706)	(121,914)	(560,754)	(549,938)
Income tax benefit	(44,629)	(45,691)	(196,908)	(225,694)
Net loss from continuing operations	(92,077)	(76,223)	(363,846)	(324,244)
Net income (loss) from discontinued operations	(20)	(2)	(21)	(2)
Net loss	(92,097)	(76,225)	(363,867)	(324,246)
Other comprehensive income (loss)	1,759	(4,641)	(4,130)	(22,589)
Comprehensive loss	(90,338)	(80,866)	(367,997)	(346,835)
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Selling, general and administrative		120		3,535
Total operating expenses		120		3,535
Other income, net		1		1,731
Interest expense on borrowings	0	0	0	0
Other income, net	(106,332)	(78,609)	(379,767)	(326,631)
Loss from continuing operations before income tax benefit	(106,332)	(78,728)	(379,767)	(328,435)
Income tax benefit	(1,818)	3,001	(5,360)	(2,040)
Net loss from continuing operations	(104,514)	(81,729)	(374,407)	(326,395)
Net income (loss) from discontinued operations	0	0	0	0
Net loss	(104,514)	(81,729)	(374,407)	(326,395)
Other comprehensive income (loss)	1,759	(4,641)	(4,130)	(22,589)
Comprehensive loss	(102,755)	(86,370)	(378,537)	(348,984)
Intersegment Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Total revenues	(13,207)	(1,567)	(13,351)	(1,688)
Cost of revenues	(8,751)	(1,565)	(8,895)	(1,685)
Selling, general and administrative	(4,456)	(2)	(4,456)	(3)
Total operating expenses	(13,207)	(1,567)	(13,351)	(1,688)
Other income, net	(24,601)	(6,567)	(31,711)	(10,350)
Interest expense on borrowings	0	0	0	0
Other income, net	117,866	67,199	424,016	336,191
Loss from continuing operations before income tax benefit	93,265	60,632	392,305	325,841
Net loss from continuing operations	93,265	60,632	392,305	325,841
Net loss	93,265	60,632	392,305	325,841
Other comprehensive income (loss)	(1,759)	4,641	4,130	31,033
Comprehensive loss	$ 91,506	$ 65,273	$ 396,435	$ 356,874