Accounts Receivable (Components Of Current Finance And Contract Receivables) (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 29, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unearned finance charges, finance receivables	$ 8.3	$ 7.6
Unearned finance charges, contract receivables	$ 9.7	$ 9.1

Deferred Discounts Finance Charges And Interest Included In Notes And Loans Receivable Current

No definition available.

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