Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2019

Investments, Debt and Equity Securities [Abstract]

Fair Value by Major Security Type

The following table summarizes, by major security type, our cash, cash equivalents, restricted cash, and marketable securities that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy (in millions):

	December 31, 2018			March 31, 2019
	Total Estimated Fair Value			Cost or Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Total Estimated Fair Value
Cash	$	10,406		$	8,635	$	—	$	—		$	8,635
Level 1 securities:
Money market funds	12,515			9,515		—		—			9,515
Equity securities (1)	170										263
Level 2 securities:
Foreign government and agency securities	815			1,382		—		—			1,382
U.S. government and agency securities	11,667			8,864		3		(13		)	8,854
Corporate debt securities	4,990			7,396		8		(6		)	7,398
Asset-backed securities	892			1,166		3		(2		)	1,167
Other fixed income securities	188			201		—		(1		)	200
Equity securities (1)	33										—
	$	41,676		$	37,159	$	14	$	(22	)	$	37,414
Less: Restricted cash, cash equivalents, and marketable securities (2)	(426		)								(394		)
Total cash, cash equivalents, and marketable securities	$	41,250									$	37,020

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(1) The related unrealized gain (loss) recorded in “Other income (expense), net” was $68 million in Q1 2019.

(2) We are required to pledge or otherwise restrict a portion of our cash, cash equivalents, and marketable securities as collateral for real estate leases, amounts due to third-party sellers in certain jurisdictions, debt, and standby and trade letters of credit. We classify cash, cash equivalents, and marketable securities with use restrictions of less than twelve months as “Accounts receivable, net and other” and of twelve months or longer as non-current “Other assets” on our consolidated balance sheets. See “Note 4 — Commitments and Contingencies.”

Investments Classified by Contractual Maturity Date

The following table summarizes the remaining contractual maturities of our cash equivalents and marketable fixed income securities as of March 31, 2019 (in millions):

	Amortized Cost		Estimated Fair Value
Due within one year	$	23,482	$	23,478
Due after one year through five years	4,274		4,277
Due after five years through ten years	190		190
Due after ten years	578		571
Total	$	28,524	$	28,516

Actual maturities may differ from the contractual maturities because borrowers may have certain prepayment conditions.

Reconciliation of cash, cash equivalents, and restricted cash

The following table provides a reconciliation of the amount of cash, cash equivalents, and restricted cash reported within the consolidated balance sheets to the total of the same such amounts shown in the consolidated statements of cash flows (in millions):

	December 31, 2018		March 31, 2019
Cash and cash equivalents	$	31,750	$	23,115
Restricted cash included in accounts receivable, net and other	418		359
Restricted cash included in other assets	5		33
Total cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows	$	32,173	$	23,507