Number of votes per share on specific matters.

No definition available.

Name:	sjm_NumberOfVotes
Namespace Prefix:	sjm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of votes per share after change in beneficial ownership.

+ References

No definition available.

+ Details

Name:	sjm_NumberOfVotesAfterChangeInBeneficialOwnership
Namespace Prefix:	sjm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of votes each holder of a common share outstanding is entitled on each matter.

+ References

No definition available.

+ Details

Name:	sjm_NumberOfVotesEachHolderOfCommonShareOutstandingIsEntitled
Namespace Prefix:	sjm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of years required to pass after change in beneficial ownership before common share is entitled to more than one vote with respect to that share.

+ References

No definition available.

+ Details

Name:	sjm_NumberofYearsRequiredtoPassAfterChangeInBeneficialOwnership
Namespace Prefix:	sjm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_EquityClassOfTreasuryStockLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow to reacquire common stock during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

+ Details

Name:	us-gaap_PaymentsForRepurchaseOfCommonStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_StockRepurchasedDuringPeriodShares
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_StockholdersEquityNoteAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ShareRepurchaseProgramAxis=sjm_A10b51PlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareRepurchaseProgramAxis=sjm_BoardAuthorizedRepurchasedPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Common Shares (Details) shares in Millions, $ in Millions	3 Months Ended	12 Months Ended
Common Shares (Details) shares in Millions, $ in Millions	Jan. 31, 2021 shares	Apr. 30, 2021 USD ($) votes_per_share shares	Apr. 30, 2020 USD ($) shares	Apr. 30, 2019 USD ($)	Oct. 31, 2020 shares	Oct. 22, 2020 shares	Jul. 31, 2020 shares
Stockholders' Equity Note [Abstract]
Number of votes each holder of a common share outstanding is entitled \| votes_per_share		1
Number of votes per share \| votes_per_share		10
Number of votes per share after change in beneficial ownership \| votes_per_share		1
Number of years required to pass after change in beneficial ownership		4 years
Equity, Class of Treasury Stock [Line Items]
Payments for shares repurchased \| $		$ 678.4	$ 4.2	$ 5.4
10b5-1 Plan
Equity, Class of Treasury Stock [Line Items]
Shares repurchased during period, shares	2.0
Board Authorized Repurchased Plan
Equity, Class of Treasury Stock [Line Items]
Shares authorized to be repurchased, shares						5.0
Shares remaining for repurchase, shares		2.8			8.6		3.6
Shares repurchased during period, shares		5.8	0.0
Payments for shares repurchased \| $		$ 671.9