FAIR VALUE MEASUREMENTS - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 25, 2020	Dec. 25, 2019
Debt Securities, Available-for-sale [Line Items]
Cost Basis	$ 87,806	$ 37,099
Total cost basis including Mutual Funds	104,513	73,535
Gross Unrealized Gains	0	72
Gross Unrealized Losses	(284)	0
Cash and cash equivalents fair value	87,806	37,099
Fair value of marketable securities	16,423	36,508
Fair Value	104,229	73,607
Level 1 \| Mutual funds
Debt Securities, Available-for-sale [Line Items]
Mutual funds	16,707	36,436
Gross Unrealized Gains	0	72
Gross Unrealized Losses	(284)	0
Fair value of marketable securities	16,423	36,508
Cash
Debt Securities, Available-for-sale [Line Items]
Cost Basis	87,806	32,094
Cash and cash equivalents fair value	87,806	32,094
Money market funds \| Level 1
Debt Securities, Available-for-sale [Line Items]
Cost Basis	0	5,005
Cash and cash equivalents fair value	$ 0	$ 5,005

Cash, Cash Equivalents, and Available-for-sale Debt and Equity Securities, Amortized Cost

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- Definition

Cash, Cash Equivalents, and Available-for-sale Securities, Amortized Cost, Fair Value

+ References

No definition available.

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- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Topic 320
-SubTopic 10
-Section 50
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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- Definition

This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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-Topic 230
-SubTopic 10
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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