FAIR VALUE MEASUREMENTS - Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets:
Cash and Cash Equivalents	$ 58,176	$ 61,688
Marketable debt securities, available-for-sale	508,675	388,557
Total	566,851	450,245
Quoted prices in active markets (Level 1)
Assets:
Cash and Cash Equivalents	58,176	61,688
Marketable debt securities, available-for-sale	0	0
Total	58,176	61,688
Significant other observable inputs (Level 2)
Assets:
Cash and Cash Equivalents	0	0
Marketable debt securities, available-for-sale	508,675	388,557
Total	508,675	388,557
Significant unobservable inputs (Level 3)
Assets:
Cash and Cash Equivalents	0	0
Marketable debt securities, available-for-sale	0	0
Total	$ 0	$ 0