Percentage of voting equity interests acquired at the acquisition date in the business combination.

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This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of assets acquired at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The number of businesses acquired by the entity during the period.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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ACQUISITIONS - Acquisition Activity (Details) $ in Thousands		3 Months Ended				12 Months Ended
	Dec. 16, 2021 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($) item company	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Acquisitions
Number of acquisitions during the period \| company						4
Contingent consideration		$ 125,808				$ 125,808	$ 28,829	$ 5,752
Goodwill recognized		698,635				698,635	248,958	$ 180,424
Intangible assets acquired		183,900				$ 183,900	$ 1,900
2021 Acquisitions
Acquisitions
Number of acquisitions during the period \| item						4
Cash consideration						$ 443,642
Stock consideration						120,571
Contingent consideration		93,304				93,304
Total consideration						657,517
Assets acquired		712,347				712,347
Liabilities assumed		476,320				476,320
Noncontrolling interest recognized		28,187				28,187
Goodwill recognized		449,677				449,677
Acquisition #1
Acquisitions
Cash consideration					$ 7,506
Contingent consideration					5,229
Total consideration					12,735
Assets acquired					504
Goodwill recognized					$ 12,231
Acquisition #2
Acquisitions
Cash consideration				$ 3,000
Contingent consideration				2,275
Total consideration				5,275
Goodwill recognized				$ 5,275
Acquisition #3 - Zellman & Associates
Acquisitions
Cash consideration			$ 53,459
Stock consideration			5,250
Total consideration			58,709
Assets acquired			22,866
Liabilities assumed			5,886
Noncontrolling interest recognized			19,569
Goodwill recognized			61,298
Intangible assets acquired			$ 14,600
Acquisition #3 - Zellman & Associates \| Zellman
Acquisitions
Ownership interest acquired			75.00%
Acquisition #4 - Alliant Capital
Acquisitions
Cash consideration	$ 379,700	379,677
Stock consideration	115,300	115,321
Contingent consideration	100,000	85,800				85,800
Total consideration	580,800	580,798
Assets acquired	688,977	688,977				688,977
Liabilities assumed	470,434	470,434				470,434
Noncontrolling interest recognized		8,618				8,618
Goodwill recognized		$ 370,873				$ 370,873
Intangible assets acquired	$ 170,800