Marketable Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities
Cash and cash equivalents	$ 109,534	$ 50,312
Investments, amortized cost	576,997	581,834
Investments	578,490	583,005
Total amortized cost	473,766
Gross unrealized gains	1,496	1,201
Gross unrealized losses	(3)	(30)
Marketable Securities	475,259
Marketable securities
Schedule of Available-for-sale Securities
Marketable Securities	475,259	550,996
Money Market Funds
Schedule of Available-for-sale Securities
Cash and cash equivalents	103,231	32,009
Corporate Securities
Schedule of Available-for-sale Securities
Total amortized cost	266,756	281,586
Gross unrealized gains	786	195
Gross unrealized losses		(30)
Marketable Securities	267,542	281,751
Government Securities
Schedule of Available-for-sale Securities
Total amortized cost	207,010	268,239
Gross unrealized gains	710	1,006
Gross unrealized losses	(3)
Marketable Securities	207,717	269,245
Cash and Cash Equivalents
Schedule of Available-for-sale Securities
Cash and cash equivalents	$ 103,231	$ 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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