Aggregate number of common shares reserved for future issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

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- Definition

The difference between the maximum number of shares reserved for future issuance and the number of shares already issued under the plan.

+ References

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- References

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- Definition

The percentage rate of participant's earnings that may be contributed each payroll period.

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SHAREHOLDERS’ EQUITY - Stock Purchase Plan (Details) - Employee Stock Purchase Plan - shares	12 Months Ended
	Dec. 27, 2019	Dec. 29, 2017	Jun. 08, 2017	Dec. 28, 2007
Employee Stock Purchase Plan
Number of shares of common stock reserved for issuance			1,125,000	300,000
Number of additional shares authorized		825,000
Purchase price per share as a percentage of fair market value	85.00%
Number of shares available for issuance	679,000
Minimum
Employee Stock Purchase Plan
Percentage of participant's earnings to be contributed under a share based compensation plan	1.00%
Maximum
Employee Stock Purchase Plan
Percentage of participant's earnings to be contributed under a share based compensation plan	10.00%