Goodwill and Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2018

Goodwill And Intangible Assets Disclosure [Abstract]

Changes in Goodwill

The following table shows the changes in goodwill by reportable segment and in total:

December 31	Mid- America Group		Southeast Group			West Group			Total
(add 000)	2018
Balance at beginning of period	$	281,403	$	50,346		$	1,828,541		$	2,160,290
Acquisitions		150,552		94,774			—			245,326
Goodwill allocated to assets held for sale		—		—			(5,571	)		(5,571	)
Divestitures		—		(927	)		—			(927	)
Balance at end of period	$	431,955	$	144,193		$	1,822,970		$	2,399,118
	2017
Balance at beginning of period	$	281,403	$	50,346		$	1,827,588		$	2,159,337
Acquisitions		—		—			230			230
Purchase price adjustments		—		—			723			723
Balance at end of period	$	281,403	$	50,346		$	1,828,541		$	2,160,290

Intangible Assets Subject to Amortization

Intangible assets subject to amortization consist of the following:

December 31	Gross Amount		Accumulated Amortization			Net Balance
(add 000)	2018
Noncompetition agreements	$	6,314	$	(6,179	)	$	135
Customer relationships		65,550		(25,575	)		39,975
Operating permits		458,951		(36,111	)		422,840
Use rights and other		16,745		(11,243	)		5,502
Trade names		12,800		(9,697	)		3,103
Total	$	560,360	$	(88,805	)	$	471,555
	2017
Noncompetition agreements	$	6,274	$	(6,144	)	$	130
Customer relationships		45,955		(17,551	)		28,404
Operating permits		458,951		(26,435	)		432,516
Use rights and other		16,745		(10,176	)		6,569
Trade names		12,800		(7,947	)		4,853
Total	$	540,725	$	(68,253	)	$	472,472

Intangible Assets Deemed to Indefinite Life and Not Being Amortized

Intangible assets deemed to have an indefinite life and not being amortized consist of the following:

December 31	Building Materials Business		Magnesia Specialties		Total
(add 000)	2018
Operating permits	$	6,600	$	—	$	6,600
Use rights		20,282		—		20,282
Trade names		280		2,565		2,845
Total	$	27,162	$	2,565	$	29,727
	2017
Operating permits	$	6,600	$	—	$	6,600
Use rights		24,432		—		24,432
Trade names		280		2,565		2,845
Total	$	31,312	$	2,565	$	33,877

Schedule of Acquired Intangibles

During 2018, the Company acquired $21,760,000 of intangible assets, consisting of the following:

(add 000, except year data)	Amount		Weighted-average amortization period
Subject to amortization:
Customer relationships	$	20,620	12 years
Noncompetition agreements		40	10 years
Total subject to amortization		20,660	12 years
Not subject to amortization:
Use rights		1,100	N/A
Total	$	21,760

Estimated Amortization Expense of Intangible Assets

The estimated amortization expense for intangible assets for each of the next five years and thereafter is as follows:

(add 000)
2019	$	13,203
2020		13,168
2021		12,462
2022		11,036
2023		10,592
Thereafter		411,094
Total	$	471,555