REVENUE FROM CONTRACTS WITH CUSTOMERS - Narrative (Details)	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2022 USD ($) segment	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Revenue from Contracts with Customers (Details) [Line Items]
Number of operating segments | segment													6
Revenues	$ 382,092,000	$ 312,117,000	$ 139,621,000	$ 246,840,000	$ 400,314,000	$ 392,281,000	$ 318,966,000	$ 443,137,000	$ 386,461,000	$ 762,103,000	$ 698,578,000	$ 1,154,384,000	$ 1,080,670,000	$ 1,554,698,000	$ 834,217,000
Accounts receivable, net	149,110,000				49,673,000								149,110,000	49,673,000
Unbilled receivables	14,144,000				12,315,000								14,144,000	12,315,000
Deferred revenue	85,441,000				69,507,000								85,441,000	69,507,000
Deferred revenue recognized													37,254,000	39,906,000	38,330,000
Capitalized contract cost	5,990,000				$ 1,605,000								5,990,000	1,605,000
Recognized expenses													3,117,000	580,000	405,000
Corporate And Reconciling Items
Revenue from Contracts with Customers (Details) [Line Items]
Revenues														0	0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue from Contracts with Customers (Details) [Line Items]
Revenue remaining performance obligation, amount	$ 54,696,000												$ 54,696,000
Expected timing of satisfaction	1 year												1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue from Contracts with Customers (Details) [Line Items]
Revenue remaining performance obligation, amount	$ 13,713,000												$ 13,713,000
Expected timing of satisfaction	1 year												1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue from Contracts with Customers (Details) [Line Items]
Revenue remaining performance obligation, amount	$ 7,994,000												$ 7,994,000
Expected timing of satisfaction	1 year												1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue from Contracts with Customers (Details) [Line Items]
Revenue remaining performance obligation, amount	$ 3,897,000												$ 3,897,000
Expected timing of satisfaction	1 year												1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue from Contracts with Customers (Details) [Line Items]
Revenue remaining performance obligation, amount	$ 1,780,000												$ 1,780,000
Expected timing of satisfaction	1 year												1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Revenue from Contracts with Customers (Details) [Line Items]
Revenue remaining performance obligation, amount	$ 3,361,000												$ 3,361,000
Expected timing of satisfaction	1 year												1 year
Auction and Liquidation segment
Revenue from Contracts with Customers (Details) [Line Items]
Revenues													$ 74,096,000	73,517,000	88,764,000
Communications Segment
Revenue from Contracts with Customers (Details) [Line Items]
Revenues													235,655,000	$ 93,347,000	$ 87,138,000
Service and Fee Revenues
Revenue from Contracts with Customers (Details) [Line Items]
Deferred revenue	$ 85,441,000												$ 85,441,000