GOODWILL AND INTANGIBLE ASSETS

12 Months Ended

Dec. 31, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

A summary of the activity and balances related to goodwill by reporting segment is as follows:


	December 31, 2018		Acquisitions		Other (1)		December 31, 2019
Eastern	$	28,154	$	2,566	$	—	$	30,720
Western	120,536		23,138		(2,619)		141,055
Recycling	12,315		—		—		12,315
Other	1,729		—		—		1,729
Total	$	162,734	$	25,704	$	(2,619)	$	185,819

(1)Relates to unregistered sale of Class A common stock that was previously held in escrow and released to us for liquidation. See Note 13, Stockholders' Equity (Deficit) for additional disclosure.


	December 31, 2017		Acquisitions		December 31, 2018
Eastern	$	19,192	$	8,962	$	28,154
Western	89,369		31,167		120,536
Recycling	12,315		—		12,315
Other	1,729		—		1,729
Total	$	122,605	$	40,129	$	162,734

A summary of intangible assets is as follows:


	Covenants Not-to-Compete		Client Lists		Total
Balance, December 31, 2019
Intangible assets	$	26,162	$	71,122	$	97,284
Less accumulated amortization	(18,968)		(19,595)		(38,563)
	$	7,194	$	51,527	$	58,721


	Covenants Not-to-Compete		Client Lists		Total
Balance, December 31, 2018
Intangible assets	$	21,750	$	44,363	$	66,113
Less accumulated amortization	(17,584)		(13,762)		(31,346)
	$	4,166	$	30,601	$	34,767

Intangible amortization expense for fiscal years 2019, 2018 and 2017 was $7,218, $3,316 and $2,061, respectively.

The intangible amortization expense estimated for the five fiscal years following fiscal year 2019 and thereafter is as follows:



Estimated Future Amortization Expense as of December 31, 2019
Fiscal year ending December 31, 2020	$	8,222
Fiscal year ending December 31, 2021	$	6,826
Fiscal year ending December 31, 2022	$	6,188
Fiscal year ending December 31, 2023	$	5,993
Fiscal year ending December 31, 2024	$	6,974
Thereafter	$	24,518