Related Party and Affiliate Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Related Party Transaction [Line Items]
Revenues	$ 16,358	$ 14,665	$ 9,256
Expenses	4,332	3,029	3,015
Self insurance expense - related party	300	500	900
The Heritage Group [Member]
Related Party Transaction [Line Items]
Revenues	8,705	8,168	4,740
Expenses	3,846	2,202	2,965
Other related parties / affiliates
Related Party Transaction [Line Items]
Revenues	7,653	6,497	4,516
Expenses	$ 486	$ 827	$ 50
Heritage Crystal Clean Inc \| The Heritage Group [Member] \| Affiliated Entity
Related Party Transaction [Line Items]
Ownership percentage	31.60%
Heritage Crystal Clean Inc \| The Fehsenfeld Family Trusts \| Affiliated Entity
Related Party Transaction [Line Items]
Ownership percentage	6.40%
Heritage Crystal Clean Inc \| Chairman Fred Fehsenfeld, Jr. \| Affiliated Entity
Related Party Transaction [Line Items]
Ownership percentage	4.30%

Cost of payments for self-insurance to related party during the period.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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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.

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=116637345&loc=SL114874292-224272

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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