Receivables - Components of Current Finance and Contract Receivables (Detail) - USD ($) $ in Millions	Sep. 29, 2018	Dec. 30, 2017
Receivables [Abstract]
Finance receivables, net of unearned finance charges of $21.4 million and $21.0 million, respectively	$ 538.2	$ 523.1
Contract receivables, net of unearned finance charges of $19.2 million and $17.6 million, respectively	106.9	98.1
Total	645.1	621.2
Allowances for doubtful accounts:
Finance receivables	(19.2)	(17.7)
Contract receivables	(1.3)	(1.3)
Total	(20.5)	(19.0)
Total current finance and contract receivables – net	624.6	602.2
Finance receivables – net	519.0	505.4
Contract receivables – net	105.6	96.8
Total current finance and contract receivables – net	624.6	602.2
Unearned finance charges, finance receivables	21.4	21.0
Unearned finance charges, contract receivable	$ 19.2	$ 17.6

Allowance for contracts receivable, current.

No definition available.

Name:	sna_AllowanceForContractsReceivableCurrent
Namespace Prefix:	sna_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Allowance for notes and loans and contract receivables current.

+ References

No definition available.

+ Details

Name:	sna_AllowanceForNotesAndLoansAndContractReceivablesCurrent
Namespace Prefix:	sna_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contract receivable, gross, current.

+ References

No definition available.

+ Details

Name:	sna_ContractReceivableGrossCurrent
Namespace Prefix:	sna_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Contract receivable net current.

+ References

No definition available.

+ Details

Name:	sna_ContractReceivableNetCurrent
Namespace Prefix:	sna_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Current notes and loans and contract receivables net.

+ References

No definition available.

+ Details

Name:	sna_CurrentNotesAndLoansAndContractReceivablesNet
Namespace Prefix:	sna_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Deferred discounts finance charges and interest included in contract receivables current.

+ References

No definition available.

+ Details

Name:	sna_DeferredDiscountsFinanceChargesAndInterestIncludedInContractReceivablesCurrent
Namespace Prefix:	sna_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Deferred discounts finance charges and interest included in notes and loans receivable current.

+ References

No definition available.

+ Details

Name:	sna_DeferredDiscountsFinanceChargesAndInterestIncludedInNotesAndLoansReceivableCurrent
Namespace Prefix:	sna_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Notes and loans and contract receivable gross current.

+ References

No definition available.

+ Details

Name:	sna_NotesAndLoansAndContractReceivableGrossCurrent
Namespace Prefix:	sna_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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

- Definition

A valuation allowance relating to a written agreement to receive money (at a specified future date(s) within one year from the reporting date (or the normal operating cycle, whichever is longer), consisting of principal as well as any accrued interest) for the portion that is expected to be uncollectible.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

+ Details

Name:	us-gaap_AllowanceForNotesAndLoansReceivableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date(s) within one year of the balance sheet date or the normal operating cycle, whichever is longer. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(a),(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4531-111522

+ Details

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

- Definition

An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4531-111522

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 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- References

No definition available.

+ Details

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