Cash and Marketable Securities

6 Months Ended

Jun. 30, 2020

Cash and Cash Equivalents [Abstract]

Cash, cash equivalents and restricted cash

A reconciliation of cash, cash equivalents, and restricted cash reported within the Condensed Consolidated Balance Sheets to the amount reported within the Condensed Consolidated Statements of Cash Flows is shown in the table below (in thousands):


	June 30,			December 31,			June 30,			December 31,
			2020			2019			2019			2018
Cash and cash equivalents	$	137,184		$	79,449		$	62,936		$	77,123
Restricted cash included within other non-current assets	1,500			1,500			1,500			1,500
Total cash, cash equivalents, and restricted cash	$	138,684		$	80,949		$	64,436		$	78,623

Marketable securities

All marketable securities were considered available-for-sale at June 30, 2020 and December 31, 2019. On a recurring basis, the Company records its marketable securities at fair value using Level 1 or Level 2 inputs as discussed in Note 2, "Fair Value Measurements". The amortized cost, gross unrealized holding gains or losses, and fair value of the Company’s marketable securities by major security type at each balance sheet date are summarized in the tables below (in thousands):


	June 30, 2020
	Amortized Cost		Unrealized Holding Gains		Unrealized Holding Losses		Aggregate Fair Value
Short-term marketable securities:
U.S. government treasuries⁽¹⁾	$	332,659	$	553	$	—	$	333,212

Corporate debt securities	49,458		303		—		49,761
Commercial paper	29,424		—		—		29,424
Total short-term marketable securities	411,541		856		—		412,397
Long-term marketable securities:

Corporate debt securities	7,127		102		—		7,229
Total long-term marketable securities	7,127		102		—		7,229
Total	$	418,668	$	958	$	—	$	419,626

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(1)Immaterial unrealized holding losses on 4 securities.


	December 31, 2019
	Amortized Cost		Unrealized Holding Gains		Unrealized Holding Losses		Aggregate Fair Value
Short-term marketable securities:
U.S. government treasuries⁽¹⁾	$	249,478	$	594	$	(2)	$	250,070
U.S. government agency securities	1,999		1		—		2,000
Corporate debt securities⁽²⁾	53,396		94		(11)		53,479
Commercial paper	30,358		—		—		30,358
Total short-term marketable securities	335,231		689		(13)		335,907
Long-term marketable securities:
U.S. government treasuries⁽³⁾	13,865		6		(2)		13,869

Corporate debt securities⁽⁴⁾	25,998		34		(15)		26,017
Total long-term marketable securities	39,863		40		(17)		39,886
Total	$	375,094	$	729	$	(30)	$	375,793

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(1)Unrealized holding losses on 2 securities with an aggregate fair value of $9.3 million.

(2)Unrealized holding losses on 4 securities with an aggregate fair value of $25.9 million.

(3)Unrealized holding losses on 1 security with an aggregate fair value of $10.1 million.

(4)Unrealized holding losses on 3 securities with an aggregate fair value of $17.2 million.

As of December 31, 2019, some of the Company’s marketable securities were in an unrealized loss position, and unrealized losses were immaterial as of June 30, 2020. The Company has not recognized an allowance for credit losses as of June 30, 2020 and there was no other-than-temporary impairment as of December 31, 2019. The Company determined that it had the ability and intent to hold all marketable securities that have been in a continuous loss position until maturity or recovery. Further, these marketable securities were initially, and continue to be, held with investment grade, high credit quality institutions. All marketable securities with unrealized losses as of each balance sheet date have been in a loss position for less than twelve months or the loss is not material.

The Company recorded unrealized gains on marketable securities as other comprehensive income in the six months ended June 30, 2020 and the three and six months ended June 30, 2019. There was no unrealized gain on marketable securities in other comprehensive income for the three months ended June 30, 2020. As a result, the Company recorded a tax benefit of $0.1 million for the six months ended June 30, 2020, and a tax benefit of $0.3 million for the three and six months ended June 30, 2019 on the Condensed Consolidated Statements of Operations and Comprehensive Loss and a corresponding tax charge in other comprehensive income.

All of the Company’s marketable securities have an effective maturity of less than two years.