BUSINESS ACQUISITIONS - Narrative (Details) - USD ($) shares in Thousands		6 Months Ended
	Apr. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Goodwill		$ 300,643,000	$ 261,767,000
CVI
Business Acquisition [Line Items]
Cash and stock paid for acquisition	$ 49,700,000
Sales contributed by acquisition		5,200,000
Net income contributed by acquisition		1,100,000
Stock issued (in shares)	352
Acquired intangible assets	$ 50,000,000
Goodwill	38,612,000
Goodwill expected to be deductible for income tax purposes	0
Fair value of accounts receivables	4,397,000
Acquisition related costs		$ 200,000
CVI | Non-compete agreements
Business Acquisition [Line Items]
Acquired intangible assets	$ 700,000
Amortization period of acquired intangible assets	5 years
CVI | Customer relationships
Business Acquisition [Line Items]
Acquired intangible assets	$ 10,700,000
Amortization period of acquired intangible assets	8 years