Condensed Consolidating Financial Statements (Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2018	Oct. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Total revenues	$ 148,871	$ 140,854	$ 294,054	$ 278,656
Cost of revenues	250,815	240,019	472,375	467,734
Selling, general and administrative	113,319	116,846	219,059	212,095
Total operating expenses	364,134	356,865	691,434	679,829
Other income (expense), net	4,464	1,011	9,006	2,231
Interest expense on external borrowings	(21,191)	(21,265)	(42,381)	(42,542)
Loss from continuing operations before income tax benefit	(231,990)	(236,265)	(430,755)	(441,484)
Income tax benefit	(61,053)	(87,953)	(111,021)	(165,354)
Net loss from continuing operations	(170,937)	(148,312)	(319,734)	(276,130)
Net income (loss) from discontinued operations	(5,339)	(5,254)	(9,212)	(8,003)
Net loss	(176,276)	(153,566)	(328,946)	(284,133)
Other comprehensive income (loss)	(2,846)	(1,385)	(4,577)	1,077
Comprehensive loss	(179,122)	(154,951)	(333,523)	(283,056)
Eliminations
Condensed Financial Statements, Captions [Line Items]
Total revenues	(4,741)	(2,911)	(7,867)	(5,759)
Cost of revenues	(2,168)	(28)	(2,759)	(143)
Selling, general and administrative	(2,573)	(2,883)	(5,108)	(5,616)
Total operating expenses	(4,741)	(2,911)	(7,867)	(5,759)
Other income (expense), net	172,829	161,239	314,112	291,068
Interest expense on external borrowings	0	0	0	0
Loss from continuing operations before income tax benefit	172,829	161,239	314,112	291,068
Net loss from continuing operations	172,829	161,239	314,112	291,068
Net loss	172,829	161,239	314,112	291,068
Other comprehensive income (loss)	2,846	1,385	4,577	(1,077)
Comprehensive loss	175,675	162,624	318,689	289,991
H&R Block, Inc. (Guarantor) | Reportable entities
Condensed Financial Statements, Captions [Line Items]
Selling, general and administrative	1,476		1,476
Total operating expenses	1,476		1,476
Other income (expense), net	(176,485)	(155,999)	(330,101)	(288,263)
Interest expense on external borrowings	0	0	0	0
Loss from continuing operations before income tax benefit	(177,961)	(155,999)	(331,577)	(288,263)
Income tax benefit	(1,685)	(2,433)	(2,631)	(4,130)
Net loss from continuing operations	(176,276)	(153,566)	(328,946)	(284,133)
Net income (loss) from discontinued operations	0	0	0	0
Net loss	(176,276)	(153,566)	(328,946)	(284,133)
Other comprehensive income (loss)	(2,846)	(1,385)	(4,577)	1,077
Comprehensive loss	(179,122)	(154,951)	(333,523)	(283,056)
Block Financial (Issuer) | Reportable entities
Condensed Financial Statements, Captions [Line Items]
Total revenues	11,458	11,705	28,290	29,261
Cost of revenues	7,014	5,104	12,047	12,964
Selling, general and administrative	2,847	3,585	6,097	6,791
Total operating expenses	9,861	8,689	18,144	19,755
Other income (expense), net	9,018	6,992	18,845	13,065
Interest expense on external borrowings	(21,126)	(21,178)	(42,249)	(42,382)
Loss from continuing operations before income tax benefit	(10,511)	(11,170)	(13,258)	(19,811)
Income tax benefit	(2,316)	(990)	(6,017)	(5,613)
Net loss from continuing operations	(8,195)	(10,180)	(7,241)	(14,198)
Net income (loss) from discontinued operations	(5,339)	(5,253)	(9,212)	(8,001)
Net loss	(13,534)	(15,433)	(16,453)	(22,199)
Comprehensive loss	(13,534)	(15,433)	(16,453)	(22,199)
Other Subsidiaries | Reportable entities
Condensed Financial Statements, Captions [Line Items]
Total revenues	142,154	132,060	273,631	255,154
Cost of revenues	245,969	234,943	463,087	454,913
Selling, general and administrative	111,569	116,144	216,594	210,920
Total operating expenses	357,538	351,087	679,681	665,833
Other income (expense), net	(898)	(11,221)	6,150	(13,639)
Interest expense on external borrowings	(65)	(87)	(132)	(160)
Loss from continuing operations before income tax benefit	(216,347)	(230,335)	(400,032)	(424,478)
Income tax benefit	(57,052)	(84,530)	(102,373)	(155,611)
Net loss from continuing operations	(159,295)	(145,805)	(297,659)	(268,867)
Net income (loss) from discontinued operations		(1)		(2)
Net loss	(159,295)	(145,806)	(297,659)	(268,869)
Other comprehensive income (loss)	(2,846)	(1,385)	(4,577)	1,077
Comprehensive loss	$ (162,141)	$ (147,191)	$ (302,236)	$ (267,792)