Goodwill and Other Intangible Assets (Tables)

12 Months Ended

Dec. 28, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

The following table shows changes to our goodwill balances by segment during the years ended December 29, 2018, and December 28, 2019:

(thousands)	Oil Business		Environmental Services		Total
Goodwill at December 30, 2017
Gross carrying amount	3,952		31,580		35,532
Accumulated impairment loss	(3,952)		—		(3,952)
Net book value at December 30, 2017	$	—	$	31,580	$	31,580
Acquisitions	—		2,543		2,543
Goodwill at December 29, 2018
Gross carrying amount	3,952		34,123		38,075
Accumulated impairment loss	(3,952)		—		(3,952)
Net book value at December 29, 2018	$	—	$	34,123	$	34,123
Acquisitions	—		639		—
Measurement period adjustments	—		(1,765)		—
Goodwill at December 28, 2019
Gross carrying amount	3,952		32,997		36,949
Accumulated impairment loss	(3,952)		—		(3,952)
Net book value at December 28, 2019	$	—	$	32,997	$	32,997

Schedule of Finite-Lived Intangible Assets

Following is a summary of software and other intangible assets:

	December 28, 2019						December 29, 2018
(thousands)	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount
Customer & supplier relationships	$	25,551	$	13,886	$	11,665	$	23,686	$	11,445	$	12,241
Software	8,093		4,887		3,206		5,040		4,094		946
Patents, formulae, and licenses	1,769		774		995		1,769		708		1,061
Non-compete agreements	3,603		3,068		535		2,937		2,904		33
Other	1,702		1,211		491		1,442		1,042		400
Total software and intangible assets	$	40,718	$	23,826	$	16,892	$	34,874	$	20,193	$	14,681

The weighted average useful lives of customer and supplier relationships are as follows:

Intangible asset	Weighted average useful life (years)
Patents, formulae, & licenses	15
Customer and supplier relationships	11
Software	9
Non-compete agreements	5
Other intangibles	7

Finite-lived Intangible Assets Amortization Expense

The estimated amortization expense for each of the five succeeding fiscal years is as follows:

Fiscal Year	Amortization Expense (millions)
2020	$3.3
2021	$3.2
2022	$2.9
2023	$2.4
2024	$0.9