Goodwill, Identifiable Intangible Assets, And Other Long-Lived Assets (Tables)

12 Months Ended

Dec. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

The changes in the carrying amount of goodwill by reportable segment during the years ended December 31, 2021 and 2020 were as follows (in thousands):


	United States electrical construction and facilities services segment		United States mechanical construction and facilities services segment		United States building services segment		United States industrial services segment		Total
Balance at December 31, 2019	$	142,545	$	299,220	$	289,158	$	332,988	$	1,063,911
Acquisitions and purchase price adjustments	—		398		12,974		—		13,372
Impairment	—		—		—		(225,500)		(225,500)
Balance at December 31, 2020	142,545		299,618		302,132		107,488		851,783
Acquisitions and purchase price adjustments	24,467		4,269		9,749		—		38,485
Intersegment transfers	(7,500)		—		900		6,600		—
Balance at December 31, 2021	$	159,512	$	303,887	$	312,781	$	114,088	$	890,268

Schedule of Intangible Assets

Identifiable intangible assets as of December 31, 2021 and 2020 consisted of the following (in thousands):


	December 31, 2021
	Gross Carrying Amount		Accumulated Amortization		Accumulated Impairment Charge		Total
Customer relationships	$	717,666	$	(374,764)	$	(4,834)	$	338,068
Trade names (unamortized)	274,721		—		(58,933)		215,788
Developed technology/Vendor network	95,661		(69,688)		—		25,973
Trade names (amortized)	32,366		(24,180)		—		8,186
Contract backlog	77,995		(76,645)		—		1,350
Total	$	1,198,409	$	(545,277)	$	(63,767)	$	589,365


	December 31, 2020
	Gross Carrying Amount		Accumulated Amortization		Accumulated Impairment Charge		Total
Customer relationships	$	670,155	$	(324,426)	$	(4,834)	$	340,895
Trade names (unamortized)	258,471		—		(58,933)		199,538
Developed technology/Vendor network	95,661		(64,994)		—		30,667
Trade names (amortized)	31,516		(23,002)		—		8,514
Contract backlog	72,045		(68,766)		—		3,279
Total	$	1,127,848	$	(481,188)	$	(63,767)	$	582,893

Schedule of Estimated Future Amortization Expense

The following table presents the estimated future amortization expense of identifiable intangible assets in the following years (in thousands):



2022	$	57,321
2023	54,891
2024	54,240
2025	53,158
2026	47,382
Thereafter	106,585
	$	373,577