INVESTMENTS AND FAIR VALUE MEASUREMENTS - Funds Held For Clients (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Fair Value Disclosures [Abstract]
Restricted cash and cash equivalents held to satisfy client funds obligations	$ 161,673	$ 147,032	$ 203,796
Restricted short-term marketable securities held to satisfy client funds obligations	6,789	9,174
Restricted long-term marketable securities held to satisfy client funds obligations	55,003	47,382
Total funds held for clients	$ 223,465	$ 203,588

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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Carrying amount as of the balance sheet date of the funds held on behalf of others and that are expected to be liquidated within one year or the normal operating cycle, if longer. This does not include funds held under reinsurance agreements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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