REVENUES (Tables)

12 Months Ended

Dec. 31, 2020

Revenue from Contract with Customer [Abstract]

We disaggregate the Company’s third-party revenues by geographic location and source of revenue as we believe these categories depict how revenue and cash flows are affected by economic factors (in thousands):


	For the year ended December 31, 2020
	Environmental Services		Safety-Kleen		Corporate		Total
Primary Geographical Markets
United States	$	1,690,256	$	1,049,975	$	(674)	$	2,739,557
Canada	313,825		89,751		964		404,540
Total third-party revenues	$	2,004,081	$	1,139,726	$	290	$	3,144,097

Sources of Revenue (1)
Technical Services	$	1,062,714	$	—	$	—	$	1,062,714
Field and Emergency Response Services	461,036		—		—		461,036
Industrial Services and Other	480,331		—		290		480,621
Safety-Kleen Environmental Services	—		809,236		—		809,236
Safety-Kleen Oil	—		330,490		—		330,490
Total third-party revenues	$	2,004,081	$	1,139,726	$	290	$	3,144,097


	For the year ended December 31, 2019
	Environmental Services		Safety-Kleen		Corporate		Total
Primary Geographical Markets
United States	$	1,721,322	$	1,220,096	$	(586)	$	2,940,832
Canada	371,041		98,595		1,722		471,358
Total third-party revenues	$	2,092,363	$	1,318,691	$	1,136	$	3,412,190

Sources of Revenue (1)
Technical Services	$	1,120,043	$	—	$	—	$	1,120,043
Field and Emergency Response Services	340,906		—		—		340,906
Industrial Services and Other (2)	631,414		—		1,136		632,550
Safety-Kleen Environmental Services	—		851,520		—		851,520
Safety-Kleen Oil	—		467,171		—		467,171
Total third-party revenues	$	2,092,363	$	1,318,691	$	1,136	$	3,412,190


	For the year ended December 31, 2018
	Environmental Services		Safety-Kleen		Corporate		Total
Primary Geographical Markets
United States	$	1,598,402	$	1,196,661	$	1,082	$	2,796,145
Canada	405,441		98,694		23		504,158
Total third-party revenues	$	2,003,843	$	1,295,355	$	1,105	$	3,300,303

Sources of Revenue (1)
Technical Services	$	1,037,388	$	—	$	—	$	1,037,388
Field and Emergency Response Services	304,727		—		—		304,727
Industrial Services and Other (3)	661,728		—		1,105		662,833
Safety-Kleen Environmental Services	—		795,077		—		795,077
Safety-Kleen Oil	—		500,278		—		500,278
Total third-party revenues	$	2,003,843	$	1,295,355	$	1,105	$	3,300,303

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(1)All revenue except oil and oil product sales within Safety-Kleen Oil and product sales within Safety-Kleen Environmental Services, which include various automotive related fluids, shop supplies and direct blended oil sales, are recognized over time. Safety-Kleen Oil and Safety-Kleen Environmental Services product sales are recognized at a point in time.

(2)Environmental Services third-party revenues of $117.0 million and Corporate third party revenues of $1.1 million previously reported as Oil, Gas and Lodging Services and Other for the year ended December 31, 2019 are now reported within Industrial Services and Other based on relative materiality to the business.

(3)Environmental Services third-party revenues of $119.8 million and Corporate third party revenues of $1.1 million previously reported as Oil, Gas and Lodging Services and Other for the year ended December 31, 2018 are now reported within Industrial Services and Other based on relative materiality to the business.

Schedule of Contract Balances

Contract Balances


(in thousands)	December 31, 2020		December 31, 2019
Receivables	$	611,534	$	644,738
Contract assets (unbilled receivables)	55,681		56,326
Contract liabilities (deferred revenue)	74,066		73,370