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Fair Value of Assets and Liabilities - Assets Measured at Fair Value (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 30, 2019 | Dec. 28, 2019 | Jun. 29, 2019 | Mar. 30, 2019 | Dec. 28, 2019 | Dec. 29, 2018 | Dec. 30, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |
Impairment charges |  | $ 4,200 | $ 200 | $ 2,800 | $ 322 | $ 2,218 | $ 0
Investments in equity securities |  | 12,969 |  |  | 12,969 | 10,312 |
Notional value |  | 16,000 |  |  | 16,000 |  |
Cash Equivalents |  | 118,999 |  |  | 118,999 |  |
Mutual funds |  | 10,464 |  |  | 10,464 | 9,112 |
Other Expense |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |
Impairment charges |  |  |  |  | 7,300 |  |
Investments in equity securities |  | 400 |  |  | 400 |  |
Level 1 |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |
Investments in equity securities |  | 12,969 |  |  | 12,969 | 10,312 |
Cash Equivalents |  | 118,999 |  |  | 118,999 |  |
Mutual funds |  | 10,464 |  |  | 10,464 | 9,112 |
Level 2 |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |
Investments in equity securities |  | 0 |  |  | 0 | 0 |
Cash Equivalents |  | 0 |  |  | 0 |  |
Mutual funds |  | 0 |  |  | 0 | 0 |
Level 3 |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |
Investments in equity securities |  | 0 |  |  | 0 | 0 |
Cash Equivalents |  | 0 |  |  | 0 |  |
Mutual funds |  | $ 0 |  |  | $ 0 | $ 0 |
Foreign Exchange Forward | Other Income |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |
Loss on change in fair value of foreign currency exchange forward contract | $ 200 |  |  |  |  |  |
Accrued Liabilities | Foreign Exchange Forward |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |
Loss on change in fair value of foreign currency exchange forward contract | $ 200 |  |  |  |  |  |

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