Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities
Cash and cash equivalents	$ 73,808	$ 50,312
Investments, amortized cost	584,807	581,834
Investments	585,873	583,005
Total amortized cost	535,007
Gross unrealized gains	1,656	1,201
Gross unrealized losses	(590)	(30)
Marketable Securities	536,073
Marketable securities
Schedule of Available-for-sale Securities
Marketable Securities	536,073	550,996
Money Market Funds
Schedule of Available-for-sale Securities
Cash and cash equivalents	49,800	32,009
Corporate Securities
Schedule of Available-for-sale Securities
Total amortized cost	333,259	281,586
Gross unrealized gains	22	195
Gross unrealized losses	(590)	(30)
Marketable Securities	332,691	281,751
Government Securities
Schedule of Available-for-sale Securities
Total amortized cost	201,748	268,239
Gross unrealized gains	1,634	1,006
Marketable Securities	203,382	269,245
Cash and Cash Equivalents
Schedule of Available-for-sale Securities
Cash and cash equivalents	$ 49,800	$ 32,009

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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