Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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Long-term debt Debt Instrument (Details) - USD ($)		6 Months Ended
Long-term debt Debt Instrument (Details) - USD ($)	Jan. 08, 2016	Jul. 02, 2016	Jul. 04, 2015	Jan. 02, 2016
Line of Credit Facility [Line Items]
Capital Lease Obligations, Noncurrent		$ 1,000		$ 71,000
Long-term Debt and Capital Lease Obligations		175,001,000		185,071,000
Letters of Credit Outstanding, Amount		300,000
Adjusted London Interbank Offered Rate (LIBOR) \| Minimum
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.125%
Adjusted London Interbank Offered Rate (LIBOR) \| Maximum
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.00%
Letter of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 50,000,000.0
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	450,000,000.0
Line of Credit Facility, Maximum Borrowing Capacity	$ 550,000,000.0
Long-term Line of Credit, Noncurrent		175,000,000		$ 185,000,000
Interest Expense, Debt		$ 1,200,000	$ 2,100,000
Revolving Credit Facility [Member] \| Base Rate \| Minimum
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.125%
Revolving Credit Facility [Member] \| Base Rate \| Maximum
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Other Foreign Currency Sublimit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 125,000,000.0
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate at Period End		1.75%
Revolving Credit Facility [Member] \| Minimum
Line of Credit Facility [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.175%
Revolving Credit Facility [Member] \| Maximum
Line of Credit Facility [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.30%
Revolving Credit Facility [Member] \| One Month Adjusted London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Revolving Credit Facility [Member] \| Federal Fund
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%