Percentage change in net revenue.

No definition available.

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- Definition

Number of Markets in which the Entity Operates.

+ References

No definition available.

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- Definition

Percentage of change in revenue.

+ References

No definition available.

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- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer, before adjustment of sales allowances. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

No definition available.

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- Definition

Refers to the number of days revenue is recognized after completion of installation.

+ References

No definition available.

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- Definition

Represents sales allowances on gross sales.

+ References

No definition available.

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- Definition

Percentage change in sales allowances.

+ References

No definition available.

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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.

+ References

No definition available.

+ Details

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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- Definition

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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REVENUE RECOGNITION - Disaggregated revenue (Details) $ in Thousands	3 Months Ended
	Mar. 30, 2019 USD ($) item	Mar. 31, 2018 USD ($)	Dec. 29, 2018 USD ($)	Dec. 31, 2017 USD ($)
Revenue Recognition
Retained earnings	$ 875,457	$ 768,223	$ 839,917
Number of markets in which the entity operates (in markets) \| item	3
Total Gross Sales	$ 1,031,605	1,011,667
Sales Allowances	(16,480)	(17,810)
Total Net Sales	$ 1,015,125	993,857
Change %	2.00%
Change % in sales allowances	(7.50%)
Change % in net sales	2.10%
North
Revenue Recognition
Total Net Sales	$ 278,333	270,186
West
Revenue Recognition
Total Net Sales	360,097	362,468
FOB Shipping Point Revenue
Revenue Recognition
Total Gross Sales	$ 996,823	981,691
Change %	1.50%
Construction Contract Revenue
Revenue Recognition
Total Gross Sales	$ 34,782	29,976
Change %	16.00%
Construction Contract Revenue \| North
Revenue Recognition
Total Gross Sales	$ 19,400	20,600
Construction Contract Revenue \| West
Revenue Recognition
Total Gross Sales	$ 15,400	$ 9,400
Minimum
Revenue Recognition
Number of days revenue is recognized	2 days
Minimum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-03-31 \| Construction Contract Revenue
Revenue Recognition
Number of months to complete contract projects	6 months
Maximum
Revenue Recognition
Number of days revenue is recognized	3 days
Maximum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-03-31 \| Construction Contract Revenue
Revenue Recognition
Number of months to complete contract projects	18 months
Adjustment \| ASU 2014-09
Revenue Recognition
Retained earnings				$ 0