3. Cash, Cash Equivalents, and Marketable Securities

3 Months Ended

Mar. 31, 2020

Cash, Cash Equivalents, and Short-term Investments [Abstract]

Cash, Cash Equivalents, and Marketable Securities

3. Cash, Cash Equivalents, and Marketable Securities

Cash, cash equivalents, and marketable securities consisted of the following at March 31, 2020 and December 31, 2019 (in thousands):

	March 31, 2020		December 31, 2019
Cash and cash equivalents:
Cash	$	929,014	$	1,345,419
Money market funds	341		7,322
Total cash and cash equivalents	929,355		1,352,741
Marketable securities:
Foreign debt	292,569		387,820
Foreign government obligations	—		22,011
U.S. debt	54,567		66,134
Time deposits	232,204		335,541
Total marketable securities	579,340		811,506
Total cash, cash equivalents, and marketable securities	$	1,508,695	$	2,164,247

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within our condensed consolidated balance sheets as of March 31, 2020 and December 31, 2019 to the total of such amounts as presented in the condensed consolidated statement of cash flows (in thousands):

	Balance Sheet Line Item	March 31, 2020		December 31, 2019
Cash and cash equivalents	Cash and cash equivalents	$	929,355	$	1,352,741
Restricted cash – current	Prepaid expenses and other current assets	47,915		13,697
Restricted cash – noncurrent	Other assets	41,608		80,072
Total cash, cash equivalents, and restricted cash		$	1,018,878	$	1,446,510

During the three months ended March 31, 2020, we sold marketable securities for proceeds of $130.8 million and realized losses of less than $0.1 million on such sales. See Note 8. “Fair Value Measurements” to our condensed consolidated financial statements for information about the fair value of our marketable securities.

The following tables summarize the unrealized gains and losses related to our available-for-sale marketable securities, by major security type, as of March 31, 2020 and December 31, 2019 (in thousands):

	As of March 31, 2020
	Amortized Cost		Unrealized Gains		Unrealized Losses		Allowance for Credit Losses		Fair Value
Foreign debt	$	298,861	$	55	$	6,250	$	97	$	292,569
U.S. debt	55,462		58		936		17		54,567
Time deposits	232,305		—		—		101		232,204
Total	$	586,628	$	113	$	7,186	$	215	$	579,340

	As of December 31, 2019
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Foreign debt	$	387,775	$	551	$	506	$	387,820
Foreign government obligations	21,991		20		—		22,011
U.S. debt	65,970		176		12		66,134
Time deposits	335,541		—		—		335,541
Total	$	811,277	$	747	$	518	$	811,506

The following table presents the change in the allowance for credit losses related to our available-for-sale marketable securities for the three months ended March 31, 2020 (in thousands):

	Marketable Securities
Balance as of December 31, 2019	$	—
Cumulative-effect adjustment for the adoption of ASU 2016-13	207
Provision for credit losses	180
Sales and maturities of marketable securities	(172)
Balance as of March 31, 2020	$	215

The contractual maturities of our marketable securities as of March 31, 2020 were as follows (in thousands):

	Fair Value
One year or less	$	320,765
One year to two years	157,337
Two years to three years	101,238
Total	$	579,340