Financial Instruments

3 Months Ended

Mar. 31, 2020

Financial Instruments, Owned, at Fair Value [Abstract]

Cash, Cash Equivalents, and Marketable Securities

The following table summarizes the Company’s cash, cash equivalents, and marketable securities and the fair value categorization of the financial instruments measured at fair value on a recurring basis:



	March 31,		December 31,
	2020		2019
	(In thousands)
Cash	$	24,850	$	33,238
Time deposits	5,044		3,924
Money market funds (Level 1)	128,213		149,624
Debt securities issued by the U.S. Treasury (Level 1)	989,934		1,040,678
Total	$	1,148,041	$	1,227,464

Cash and cash equivalents	$	498,693	$	508,196
Restricted cash (included in Other long-term assets)	9,409		9,405
Total Cash, cash equivalents, and restricted cash	508,102		517,601
Marketable securities	639,939		709,863
Total	$	1,148,041	$	1,227,464

The fair value of the debt securities held as of March 31, 2020 was $989.9 million, including $2.4 million of gross and net unrealized gains. All of the debt securities held as of March 31, 2020 are scheduled to mature in less than one year.

Fair Value Measurements

The fair value of the Company’s investments in money market funds approximates their face value. Such instruments are included in Cash and cash equivalents. The fair value of the debt securities consisting of U.S. Treasury bills is based on their quoted market prices. Debt securities purchased with original maturities in excess of three months are included in Marketable securities. The fair value of all of these financial instruments are classified as Level 1 in the fair value hierarchy.

The Company’s other financial instruments include cash, accounts receivable, restricted cash, and accounts payable. As of March 31, 2020, the carrying value of these financial instruments approximated their fair value. The fair values of the senior notes due 2023, 2025, and 2027 were $751.6 million, $511.6 million, and $575.0 million, respectively, as of March 31, 2020. The fair values of these debt instruments are based on available market information from public data sources and are classified as Level 2.