Fair Value of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Jan. 03, 2015	Dec. 28, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of marketable securities	$ 139,233	$ 106,746
Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Foreign currency forward exchange contracts, net	0	0
Total fair value of financial instruments	139,233	101,505
Level 1 | Short Term
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of marketable securities	139,233	101,505
Level 1 | Long Term
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of marketable securities	0	0
Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Foreign currency forward exchange contracts, net	414	48
Total fair value of financial instruments	414	48
Level 2 | Short Term
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of marketable securities	0	0
Level 2 | Long Term
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of marketable securities	0	0
Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Foreign currency forward exchange contracts, net	0	0
Total fair value of financial instruments	0	5,241
Level 3 | Short Term
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of marketable securities	0	0
Level 3 | Long Term
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of marketable securities	0	5,241
Estimate of Fair Value Measurement [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Foreign currency forward exchange contracts, net	414	48
Total fair value of financial instruments	139,647	106,794
Estimate of Fair Value Measurement [Member] | Short Term
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of marketable securities	139,233	101,505
Estimate of Fair Value Measurement [Member] | Long Term
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of marketable securities	$ 0	$ 5,241