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FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Financial assets and liabilities measured at fair value (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2025	Dec. 31, 2024	Aug. 31, 2024
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Investment securities		$ 9,157
Realized gain	$ 19
Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Money Market Funds	252,658	276,374
Investment securities	15,000
Prices in active markets for identical assets (Level 1) \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Money Market Funds	252,658	276,374
Significant unobservable inputs (Level 3) \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Investment securities	15,000
Commercial paper \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Investment securities		4,920
Commercial paper \| Significant other observable inputs (Level 2) \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Investment securities		4,920
Corporate bonds \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Investment securities		250
Corporate bonds \| Significant other observable inputs (Level 2) \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Investment securities		250
U.S. Treasury securities \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Investment securities		5,983
U.S. Treasury securities \| Significant other observable inputs (Level 2) \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Investment securities		5,983
Tellutax
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Contingent consideration	0	0
Ecosio \| Cash Earn-outs
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Contingent consideration	77,900	74,400	$ 71,000
Ecosio \| Cash Earn-outs \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Contingent consideration	77,900	74,400
Ecosio \| Cash Earn-outs \| Significant unobservable inputs (Level 3) \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Contingent consideration	77,900	74,400
Ecosio \| Stock Earn-outs
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Contingent consideration	32,200	48,100	$ 34,000
Ecosio \| Stock Earn-outs \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Contingent consideration	32,200	48,100
Ecosio \| Stock Earn-outs \| Significant unobservable inputs (Level 3) \| Fair Value, Recurring
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Contingent consideration	$ 32,200	$ 48,100