Condensed Consolidating Financial Statements (Income Statement) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2016	Oct. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Total revenues	$ 131,332	$ 128,415	$ 256,517	$ 266,133
Cost of revenues	225,702	226,401	436,788	439,909
Selling, general and administrative	113,652	135,847	212,475	234,039
Total operating expenses	339,354	362,248	649,263	673,948
Other income, net	2,180	10,505	5,148	10,938
Interest expense on borrowings	(22,620)	(14,181)	(44,086)	(22,756)
Other income, net	(7)	(210)	(334)	(5,195)
Loss from continuing operations before income tax benefit	(228,469)	(237,719)	(432,018)	(424,828)
Income tax benefit	(85,054)	(95,201)	(167,577)	(185,805)
Net loss from continuing operations	(143,415)	(142,518)	(264,441)	(239,023)
Net income (loss) from discontinued operations	(2,805)	(2,489)	(5,452)	(5,643)
Net loss	(146,220)	(145,007)	(269,893)	(244,666)
Other comprehensive income (loss)	(2,318)	(7,974)	(5,889)	(17,948)
Comprehensive loss	(148,538)	(152,981)	(275,782)	(262,614)
Block Financial Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Total revenues	10,934	13,972	26,438	38,739
Cost of revenues	5,666	9,810	14,272	21,565
Selling, general and administrative	1,732	13,374	4,212	17,750
Total operating expenses	7,398	23,184	18,484	39,315
Other income, net	2,256	11,040	5,935	11,535
Interest expense on borrowings	(22,248)	(14,085)	(43,562)	(22,521)
Other income, net	(1,049)	(276)	(3,902)	(744)
Loss from continuing operations before income tax benefit	(17,505)	(12,533)	(33,575)	(12,306)
Income tax benefit	(5,962)	(4,047)	(11,756)	(761)
Net loss from continuing operations	(11,543)	(8,486)	(21,819)	(11,545)
Net income (loss) from discontinued operations	(2,805)	(2,489)	(5,451)	(5,643)
Net loss	(14,348)	(10,975)	(27,270)	(17,188)
Other comprehensive income (loss)		(7,257)		(8,444)
Comprehensive loss	(14,348)	(18,232)	(27,270)	(25,632)
Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total revenues	120,423	114,471	230,223	227,515
Cost of revenues	220,061	216,618	422,660	418,464
Selling, general and administrative	111,920	119,059	208,263	212,875
Total operating expenses	331,981	335,677	630,923	631,339
Other income, net	1,639	902	6,323	1,456
Interest expense on borrowings	(372)	(96)	(524)	(235)
Other income, net	(14,833)	(13,166)	(29,147)	(25,421)
Loss from continuing operations before income tax benefit	(225,124)	(233,566)	(424,048)	(428,024)
Income tax benefit	(76,539)	(88,138)	(152,279)	(180,003)
Net loss from continuing operations	(148,585)	(145,428)	(271,769)	(248,021)
Net income (loss) from discontinued operations			(1)
Net loss	(148,585)	(145,428)	(271,770)	(248,021)
Other comprehensive income (loss)	(2,318)	(7,974)	(5,889)	(17,948)
Comprehensive loss	(150,903)	(153,402)	(277,659)	(265,969)
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Selling, general and administrative		3,415		3,415
Total operating expenses		3,415		3,415
Other income, net		821		1,730
Interest expense on borrowings	0	0	0	0
Other income, net	(148,773)	(145,429)	(273,435)	(248,022)
Loss from continuing operations before income tax benefit	(148,773)	(148,023)	(273,435)	(249,707)
Income tax benefit	(2,553)	(3,016)	(3,542)	(5,041)
Net loss from continuing operations	(146,220)	(145,007)	(269,893)	(244,666)
Net income (loss) from discontinued operations	0	0	0	0
Net loss	(146,220)	(145,007)	(269,893)	(244,666)
Other comprehensive income (loss)	(2,318)	(7,974)	(5,889)	(17,948)
Comprehensive loss	(148,538)	(152,981)	(275,782)	(262,614)
Intersegment Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Total revenues	(25)	(28)	(144)	(121)
Cost of revenues	(25)	(27)	(144)	(120)
Selling, general and administrative		(1)		(1)
Total operating expenses	(25)	(28)	(144)	(121)
Other income, net	(1,715)	(2,258)	(7,110)	(3,783)
Interest expense on borrowings	0	0	0	0
Other income, net	164,648	158,661	306,150	268,992
Loss from continuing operations before income tax benefit	162,933	156,403	299,040	265,209
Net loss from continuing operations	162,933	156,403	299,040	265,209
Net loss	162,933	156,403	299,040	265,209
Other comprehensive income (loss)	2,318	15,231	5,889	26,392
Comprehensive loss	$ 165,251	$ 171,634	$ 304,929	$ 291,601