Cash and Investments in Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Cash and Investments in Marketable Securities, Including Cash Equivalents

Cash and investments in marketable securities, including cash equivalents, are as follows (in thousands):

	Estimated Fair Value at
	March 31, 2021		December 31, 2020
Cash and cash equivalents	$	150,164	$	198,955
Short-term investments	887,152		862,941
Long-term investments	96,093		136,662
Total cash and investments in marketable securities	$	1,133,409	$	1,198,558

Portfolio of Cash and Investments in Marketable Securities

Our portfolio of cash and investments in marketable securities includes (in thousands):

	March 31, 2021								December 31, 2020
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Fair Value
Corporate notes and bonds	$	510,521	$	313	$	(171)	$	510,663	$	687,469
Corporate commercial paper	478,448		35		(41)		478,442		313,497
Obligations of U.S. government agencies	4,880		4		—		4,884		2,382
Available-for-sale investments	$	993,849	$	352	$	(212)	$	993,989	$	1,003,348
Money market funds							123,607		179,302
Certificates of deposit							8,254		9,623
Cash							7,559		6,285
Total cash and investments in marketable securities							$	1,133,409	$	1,198,558