Receivables (Narrative) (Details) - USD ($) $ in Millions	Jul. 31, 2018	Jul. 31, 2017
Loans to franchisees
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans more than 90 days past due	$ 1.2	$ 0.9
Instant Cash Back® receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balances more than 60 days old	1.4	$ 1.2
Instant Cash Back® receivables \| 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loan balances	4.6
Instant Cash Back® receivables \| 2016 and prior
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loan balances	$ 1.2

Notes, Loans, and Financing Receivable, Recorded Investment, 60 or more Days Past Due

No definition available.

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Namespace Prefix:	hrb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

+ Details

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Period Type:	instant

- Details

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- Details

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- Details

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- Details

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