EMPLOYEE BENEFIT PLANS (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($) multiemployer_plan	Jan. 01, 2015 USD ($)	Dec. 26, 2013 USD ($)
Defined Contribution Plan
Employee contribution limit per calendar year (as a percent of compensation)	50.00%
Employer match of employee contributions of first 3% of eligible compensation (as a percent)	100.00%
Percentage of eligible compensation, matched 100% by employer (as a percent)	3.00%
Employer match of employee contributions of next 2% of eligible compensation (as a percent)	50.00%
Percentage of eligible compensation, matched 50% by employer (as a percent)	2.00%
Matching contributions made by the entity during the period	$ 3.3	$ 3.3	$ 3.1
Union-Sponsored Plans [Abstract]
Company contributions (less than)	$ 0.1	$ 0.1	$ 0.1
Local 160
Union-Sponsored Plans [Abstract]
Number of plans \| multiemployer_plan	5
Estimated withdrawal liability	$ 0.6

The limit of annual employee contributions to the plan per calendar year as a percentage of compensation.

No definition available.

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- Definition

Represents the first level of employee contributions (percentage of compensation) which are matched by the employer.

+ References

No definition available.

+ Details

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- Definition

Represents the second level of employee contributions (percentage of compensation) which are matched by the employer.

+ References

No definition available.

+ Details

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- Definition

Represents the employer matching contribution of the first level of employee contributions.

+ References

No definition available.

+ Details

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- Definition

Represents the employer matching contribution of the second level of employee contributions.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Multiemployer Plan, Number of Plans

+ References

No definition available.

+ Details

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- Definition

Union-Sponsored Plans [Abstract]

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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Period Type:	duration

- Definition

Amount of contributions made to multiemployer plans by the employer. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49170332&loc=SL14450702-114947

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=49170332&loc=SL14450691-114947

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=49170332&loc=SL14450657-114947

+ Details

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Period Type:	duration

- Definition

Amount of the obligation recognized by withdrawing from a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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