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

The period of time invoices are due.

+ References

No definition available.

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- Definition

Percentage of change in revenue.

+ References

No definition available.

+ Details

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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, net 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.

+ Details

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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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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Revenue Recognition (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 29, 2018 USD ($) item	Sep. 29, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jul. 01, 2017 USD ($)	Apr. 01, 2017 USD ($)	Dec. 29, 2018 USD ($) item	Dec. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)
Revenue Recognition
Retained earnings	$ 839,917				$ 736,212				$ 839,917	$ 736,212
Number of markets in which the entity operates (in markets) \| item	3								3
Total Gross Sales									$ 4,565,749	4,006,203	$ 3,297,377
Sales Allowances									(76,569)	(65,021)
Total Net Sales	$ 988,179	$ 1,212,702	$ 1,294,440	$ 993,857	$ 966,091	$ 1,056,586	$ 1,072,375	$ 846,130	$ 4,489,180	3,941,182	$ 3,240,493
Change %									14.00%
Change % in sales allowances									17.80%
Change % in net sales									13.90%
FOB Shipping Point Revenue
Revenue Recognition
Total Gross Sales									$ 4,440,098	3,867,781
Change %									14.80%
Construction Contract Revenue
Revenue Recognition
Total Gross Sales									$ 125,651	$ 138,422
Change %									(9.20%)
Construction Contract Revenue \| North
Revenue Recognition
Total Gross Sales									$ 77,800
Construction Contract Revenue \| West
Revenue Recognition
Total Gross Sales									$ 47,800
Minimum
Revenue Recognition
Number of days revenue is recognized									2 days
Period of time invoices are due									45 days
Minimum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-12-30 \| Construction Contract Revenue
Revenue Recognition
Number of months to complete contract projects	6 months								6 months
Maximum
Revenue Recognition
Number of days revenue is recognized									3 days
Period of time invoices are due									60 days
Maximum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-12-30 \| Construction Contract Revenue
Revenue Recognition
Number of months to complete contract projects	18 months								18 months
Adjustment \| ASU 2014-09
Revenue Recognition
Retained earnings												$ 0