Employee Benefit Plan	12 Months Ended
Dec. 28, 2019
Postemployment Benefits [Abstract]
Employee Benefit Plan	EMPLOYEE BENEFIT PLANHeritage-Crystal Clean offers a defined contribution benefit plan for its employees who are immediately eligible to participate in the plan. Participants are allowed to contribute 1% to 70% of their pre-tax earnings to the plan. The Company matches 100% of the first 3% contributed by the participant and 50% of the next 2% contributed by the participant for a maximum contribution of 4% per participant. The Company's matching contribution under this plan was $2.6 million, $2.0 million, and $1.8 million in fiscal 2019, 2018, and 2017, respectively.

The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.

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-Name Accounting Standards Codification
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