Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

As of December 31, goodwill was as follows:

	Integrated Agencies Network		Brand Performance Network		Communications Network		All Other		Total
Balance at December 31, 2020	$	95,164	$	180,639	$	49,533	$	26,389	$	351,725
Acquired goodwill	1,058,411		178,994		66,244		—		1,303,649
Disposition	—		—		—		(935)		(935)
Foreign currency translation	(502)		(1,020)		—		(194)		(1,716)
Balance at December 31, 2021	$	1,153,073	$	358,613	$	115,777	$	25,260	$	1,652,723
Acquired goodwill	3,330		26,176		6,569		29,387		65,462
Impairment	(49,840)		(49,314)		—		(17,560)		(116,714)
Transfer of goodwill between segments (1)	(111,065)		111,065		—		—		—
Foreign currency translation	(11,422)		(13,467)		(753)		—		(25,642)
Other (2)	(15,682)		685		6,124		—		(8,873)
Balance at December 31, 2022	$	968,394	$	433,758	$	127,717	$	37,087	$	1,566,956
Acquired goodwill	18,451		2,626		—		—		21,077
Disposition - ConcentricLife	(98,779)		—		—		—		(98,779)
Transfer of goodwill between segments (1)	(8,517)		—		8,517		—		—
Foreign currency translation	1,846		5,056		353		271		7,526
Other (2)	—		220		—		1,815		2,035
Balance at December 31, 2023	$	881,395	$	441,660	$	136,587	$	39,173	$	1,498,815

Schedule of Intangible Assets and Goodwill

The gross and net amounts of intangible assets other than goodwill as of December 31, are as follows:

Intangible Assets	2023		2022
Customer relationships, gross	$	870,987	$	875,160
Accumulated amortization	(218,808)		(150,655)
Customer relationships, net	$	652,179	$	724,505
Trade names, gross	$	188,820	$	197,037
Accumulated amortization	(74,141)		(53,150)
Trade names, net	$	114,679	$	143,887
Capitalized software, gross	$	70,622	$	42,234
Accumulated amortization	(30,928)		(18,591)
Capitalized software, net	$	39,694	$	23,643
Developed technology and other, gross	$	21,583	$	21,331
Accumulated amortization	(9,915)		(5,837)
Developed technology and other, net	$	11,668	$	15,494
Total intangible assets, gross	$	1,152,012	$	1,135,762
Accumulated amortization	(333,792)		(228,233)
Total intangible assets, net	$	818,220	$	907,529

T

Finite-Lived Intangible Assets Amortization Expense

The estimated amortization expense for the five succeeding years is as follows:

Year	Amortization
2024	$	106,514
2025	99,091
2026	89,824
2027	79,256
2028	71,734
Thereafter	371,801