Goodwill and other intangible assets

9 Months Ended

Sep. 30, 2022

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and other intangible assets

Goodwill and other intangible assets

The changes in the carrying amount of goodwill were as follows:

	Balance at January 1, 2022		Goodwill Acquired During  the Year		Measurement Period Adjustments		Balance at September 30, 2022
	(In thousands)
Natural gas distribution	$	345,736	$	—	$	—	$	345,736
Construction materials and contracting	276,426		—		(2,124)		274,302
Construction services	143,224		—		—		143,224
Total	$	765,386	$	—	$	(2,124)	$	763,262

	Balance at January 1, 2021		Goodwill Acquired During the Year		Measurement Period Adjustments		Balance at September 30, 2021
	(In thousands)
Natural gas distribution	$	345,736	$	—	$	—	$	345,736
Construction materials and contracting	226,003		2,900		(217)		228,686
Construction services	143,224		—		—		143,224
Total	$	714,963	$	2,900	$	(217)	$	717,646

	Balance at January 1, 2021		Goodwill Acquired During the Year		Measurement Period Adjustments		Balance at December 31, 2021
	(In thousands)
Natural gas distribution	$	345,736	$	—	$	—	$	345,736
Construction materials and contracting	226,003		50,640		(217)		276,426
Construction services	143,224		—		—		143,224
Total	$	714,963	$	50,640	$	(217)	$	765,386

Other amortizable intangible assets were as follows:

	September 30, 2022		September 30, 2021		December 31, 2021
	(In thousands)
Customer relationships	$	28,990	$	29,423	$	29,740
Less accumulated amortization	12,768		9,705		10,650
	16,222		19,718		19,090
Noncompete agreements	4,591		3,991		4,591
Less accumulated amortization	3,377		2,710		2,856
	1,214		1,281		1,735
Other	5,279		11,957		12,601
Less accumulated amortization	3,970		10,715		10,848
	1,309		1,242		1,753
Total	$	18,745	$	22,241	$	22,578

The previous tables include goodwill and intangible assets associated with the business combinations completed during 2021. For more information related to these business combinations, see Note 10.

Amortization expense for amortizable intangible assets for the three and nine months ended September 30, 2022, was $1.3 million and $3.8 million, respectively. Amortization expense for amortizable intangible assets for the three and nine months ended September 30, 2021, was $1.2 million and $3.9 million, respectively. Estimated amortization expense for identifiable intangible assets as of September 30, 2022, was:

	Remainder of 2022		2023		2024		2025		2026		Thereafter
	(In thousands)
Amortization expense	$	1,159	$	4,591	$	4,249	$	2,200	$	1,781	$	4,765