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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 320
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Paragraph 9
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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
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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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No definition available.

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INVESTMENTS IN SECURITIES (Details) - USD ($)	3 Months Ended		9 Months Ended
INVESTMENTS IN SECURITIES (Details) - USD ($)	Sep. 24, 2017	Sep. 25, 2016	Sep. 24, 2017	Sep. 25, 2016	Dec. 25, 2016
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sale or maturity of available-for-sale securities			$ 0	$ 0
Available-for-sale securities, gross realized gain (loss)	$ 0	$ 0	0	$ 0
Fixed income securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	155,216,000		155,216,000		$ 140,480,000
Fair Value	155,216,000		155,216,000		140,480,000
Other
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	62,000		62,000		61,000
Fair Value	$ 62,000		$ 62,000		$ 61,000