Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities
Cash and cash equivalents	$ 176,965	$ 163,544
Investments, amortized cost	559,203	594,038
Investments	559,310	594,123
Total amortized cost	393,853
Gross unrealized gains	119	94
Gross unrealized losses	(12)	(9)
Marketable Securities	393,960
Marketable securities
Schedule of Available-for-sale Securities
Marketable Securities	393,960	435,186
Money Market Funds
Schedule of Available-for-sale Securities
Cash and cash equivalents	165,350	158,937
Corporate Securities
Schedule of Available-for-sale Securities
Total amortized cost	73,922	119,782
Gross unrealized gains	12	57
Gross unrealized losses	(5)	(6)
Marketable Securities	73,929	119,833
Government Securities
Schedule of Available-for-sale Securities
Total amortized cost	319,931	315,319
Gross unrealized gains	107	37
Gross unrealized losses	(7)	(3)
Marketable Securities	320,031	315,353
Cash and Cash Equivalents
Schedule of Available-for-sale Securities
Cash and cash equivalents	$ 165,350	$ 158,937

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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