CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS - Cash and Cash Equivalents and Short-Term Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents	$ 367,014	$ 208,802
AFS Securities
Adjusted cost basis	147,900
Unrealized gains	11
Unrealized losses	(780)
Debt securities, fair market value and recorded basis	147,131
HTM Securities
Debt securities, held-to-maturity, Adjusted cost basis and Recorded basis	89,945	304,804
Unrealized gains	0	8
Unrealized losses	(213)	0
Fair market value	89,732	304,812
Debt securities, available-for-sale and held-to-maturity, Adjusted cost basis	949,286	937,700
Debt securities, available-for-sale and held-to-maturity, Unrealized gains	11	8
Debt securities, available-for-sale and held-to-maturity, Unrealized losses	(993)	0
Debt securities, available-for-sale and held-to-maturity, fair value	948,304	937,708
Debt securities, available-for-sale and held-to-maturity	948,517	937,700
Cash and Cash Equivalents
AFS Securities
Debt securities, fair market value and recorded basis	1,514
HTM Securities
Debt securities, available-for-sale and held-to-maturity	367,014	208,802
Short-Term Investments
AFS Securities
Debt securities, fair market value and recorded basis	145,617
HTM Securities
Debt securities, held-to-maturity, Adjusted cost basis and Recorded basis	89,945	304,804
Debt securities, available-for-sale and held-to-maturity	581,503	728,898
Level 1 \| U.S. Treasury bills
AFS Securities
Adjusted cost basis	547
Unrealized gains	0
Unrealized losses	(10)
Debt securities, fair market value and recorded basis	537
Level 1 \| U.S. Treasury bills \| Short-Term Investments
AFS Securities
Debt securities, fair market value and recorded basis	537
Level 2 \| U.S. Treasury bills
HTM Securities
Debt securities, held-to-maturity, Adjusted cost basis and Recorded basis		199,981
Unrealized gains		8
Unrealized losses		0
Fair market value		199,989
Level 2 \| U.S. Treasury bills \| Short-Term Investments
HTM Securities
Debt securities, held-to-maturity, Adjusted cost basis and Recorded basis		199,981
Level 2 \| Government and governmental agencies
AFS Securities
Adjusted cost basis	7,786
Unrealized gains	0
Unrealized losses	(32)
Debt securities, fair market value and recorded basis	7,754
Level 2 \| Government and governmental agencies \| Short-Term Investments
AFS Securities
Debt securities, fair market value and recorded basis	7,754
Level 2 \| Corporate debt securities
AFS Securities
Adjusted cost basis	139,567
Unrealized gains	11
Unrealized losses	(738)
Debt securities, fair market value and recorded basis	138,840
HTM Securities
Debt securities, held-to-maturity, Adjusted cost basis and Recorded basis	89,945	104,823
Unrealized gains	0	0
Unrealized losses	(213)	0
Fair market value	89,732	104,823
Level 2 \| Corporate debt securities \| Cash and Cash Equivalents
AFS Securities
Debt securities, fair market value and recorded basis	1,514
Level 2 \| Corporate debt securities \| Short-Term Investments
AFS Securities
Debt securities, fair market value and recorded basis	137,326
HTM Securities
Debt securities, held-to-maturity, Adjusted cost basis and Recorded basis	89,945	104,823
Cash
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents, fair value	7,173	3,139
Cash \| Cash and Cash Equivalents
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents	7,173	3,139
Money market funds \| Level 1
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents, fair value	217,498	64,668
Money market funds \| Level 1 \| Cash and Cash Equivalents
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents	217,498	64,668
Certificate of deposits and term deposits \| Level 2
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents, fair value	486,770	565,089
Certificate of deposits and term deposits \| Level 2 \| Cash and Cash Equivalents
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents	140,829	140,995
Certificate of deposits and term deposits \| Level 2 \| Short-Term Investments
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents	$ 345,941	$ 424,094

Cash, Cash Equivalents, Available-for-sale, And Held To Maturity Debt Securities

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Cash, Cash Equivalents, Available-for-sale, And Held To Maturity Debt Securities, Amortized Cost

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Cash, Cash Equivalents, Available-for-sale, And Held To Maturity Debt Securities, Fair Value

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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).

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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.

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Amount of cumulative unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of cumulative unrecognized loss on investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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