INCOME TAXES - Unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017
Unrecognized tax benefits (excluding interest and penalties)
Balance, beginning of year	$ 1,064	$ 897
Gross increases related to current year tax positions	1,350	141
Gross increases related to prior year tax positions		26
Gross decreases related to prior year tax positions	(14)
Lapse of statute of limitations	(19)
Balance, end of year	2,381	$ 1,064
Liability of interest and penalties related to unrecognized tax benefits	$ 100

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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