Cash, Cash Equivalents, and Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2015

Investments, Debt and Equity Securities [Abstract]

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



	June 30, 2015										December 31, 2014
	Cost or Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Total Estimated Fair Value			Total Estimated Fair Value
Cash	$	4,368	$	—	$	—		$	4,368		$	4,155
Level 1 securities:
Money market funds	6,056		—		—			6,056			10,718
Equity securities	4		18		—			22			4
Level 2 securities:
Foreign government and agency securities	63		—		—			63			80
U.S. government and agency securities	3,037		2		(2		)	3,037			2,406
Corporate debt securities	468		1		(1		)	468			401
Asset-backed securities	111		—		—			111			69
Other fixed income securities	44		—		—			44			33
	$	14,151	$	21	$	(3	)	$	14,169		$	17,866
Less restricted cash, cash equivalents, and marketable securities (1)								(168		)	(450		)
Total cash, cash equivalents, and marketable securities								$	14,001		$	17,416

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(1)

We are required to pledge or otherwise restrict a portion of our cash, cash equivalents, and marketable securities as collateral for standby and trade letters of credit, guarantees, debt, real estate leases, and amounts due to third-party sellers in certain jurisdictions. 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 3 — Commitments and Contingencies.”

Investments Classified by Contractual Maturity Date

The following table summarizes the contractual maturities of our cash equivalents and marketable fixed-income securities as of June 30, 2015 (in millions):



	Amortized Cost		Estimated Fair Value
Due within one year	$	8,230	$	8,230
Due after one year through five years	1,218		1,218
Due after five years through ten years	145		145
Due after ten years	186		186
Total	$	9,779	$	9,779