Fair Value Measurements (Assets) (Details) - USD ($) $ in Thousands | Mar. 30, 2019 | Dec. 29, 2018 |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents (including money market funds) | $ 47,872 | $ 76,819 |
Fair value, measurements, recurring | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents (including money market funds) | 47,872 | 76,819 |
Derivative financial instruments | 2,810 | 3,797 |
Deferred stock-based compensation | 8,915 | 7,857 |
Fair value, measurements, recurring | Quoted prices in active markets for identical assets (Level 1) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents (including money market funds) | 47,872 | 76,819 |
Derivative financial instruments | 0 | 0 |
Deferred stock-based compensation | 0 | 0 |
Fair value, measurements, recurring | Significant other observable inputs (Level 2) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents (including money market funds) | 0 | 0 |
Derivative financial instruments | 2,810 | 3,797 |
Deferred stock-based compensation | 8,915 | 7,857 |
Fair value, measurements, recurring | Significant unobservable inputs (Level 3) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents (including money market funds) | 0 | 0 |
Derivative financial instruments | 0 | 0 |
Deferred stock-based compensation | 0 | 0 |
Fair value, measurements, recurring | Government securities | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Available-for-sale debt securities | 7,447 | 7,384 |
Fair value, measurements, recurring | Government securities | Quoted prices in active markets for identical assets (Level 1) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Available-for-sale debt securities | 0 | 0 |
Fair value, measurements, recurring | Government securities | Significant other observable inputs (Level 2) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Available-for-sale debt securities | 7,447 | 7,384 |
Fair value, measurements, recurring | Government securities | Significant unobservable inputs (Level 3) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Available-for-sale debt securities | 0 | 0 |
Fair value, measurements, recurring | Corporate Bonds | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Available-for-sale debt securities | 4,218 | 4,620 |
Fair value, measurements, recurring | Corporate Bonds | Quoted prices in active markets for identical assets (Level 1) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Available-for-sale debt securities | 0 | 0 |
Fair value, measurements, recurring | Corporate Bonds | Significant other observable inputs (Level 2) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Available-for-sale debt securities | 4,218 | 4,620 |
Fair value, measurements, recurring | Corporate Bonds | Significant unobservable inputs (Level 3) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Available-for-sale debt securities | 0 | 0 |
Variable Rate Debt Obligation | Fair value, measurements, recurring | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fair value of debt obligations | 196,500 | 150,000 |
Variable Rate Debt Obligation | Fair value, measurements, recurring | Quoted prices in active markets for identical assets (Level 1) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fair value of debt obligations | 0 | 0 |
Variable Rate Debt Obligation | Fair value, measurements, recurring | Significant other observable inputs (Level 2) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fair value of debt obligations | 196,500 | 150,000 |
Variable Rate Debt Obligation | Fair value, measurements, recurring | Significant unobservable inputs (Level 3) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fair value of debt obligations | 0 | 0 |
Fixed Rate Debt Obligation | Fair value, measurements, recurring | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fair value of debt obligations | 100,000 | 100,000 |
Fixed Rate Debt Obligation | Fair value, measurements, recurring | Quoted prices in active markets for identical assets (Level 1) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fair value of debt obligations | 0 | 0 |
Fixed Rate Debt Obligation | Fair value, measurements, recurring | Significant other observable inputs (Level 2) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fair value of debt obligations | 100,000 | 100,000 |
Fixed Rate Debt Obligation | Fair value, measurements, recurring | Significant unobservable inputs (Level 3) | | |
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fair value of debt obligations | $ 0 | $ 0 |