AMAZON COM INC | 2013 | FY | 3

CASH, CASH EQUIVALENTS, AND MARKETABLE SECURITIES
As of December 31, 2013 and 2012, our cash, cash equivalents, and marketable securities primarily consisted of cash, U.S. and foreign government and agency securities, AAA-rated money market funds, and other investment grade securities. Cash equivalents and marketable securities are recorded at fair value. 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):
 
 
December 31, 2013
  
Cost or
Amortized
Cost
 
Gross
Unrealized
Gains
 
Gross
Unrealized
Losses
 
Total
Estimated
Fair Value
Cash
$
3,008

 
$
—

 
$
—

 
$
3,008

Level 1 securities:
 
 
 
 
 
 
 
Money market funds
5,914

 
—

 
—

 
5,914

Equity securities
3

 
1

 
—

 
4

Level 2 securities:
 
 
 
 
 
 
 
Foreign government and agency securities
757

 
2

 
(1
)
 
758

U.S. government and agency securities
2,224

 
1

 
(3
)
 
2,222

Corporate debt securities
739

 
3

 
(1
)
 
741

Asset-backed securities
65

 
—

 
—

 
65

Other fixed income securities
36

 
—

 
—

 
36

 
$
12,746

 
$
7

 
$
(5
)
 
$
12,748

Less: Restricted cash, cash equivalents, and marketable securities (1)
 
 
 
 
 
 
(301
)
Total cash, cash equivalents, and marketable securities
 
 
 
 
 
 
$
12,447

 
December 31, 2012
  
Cost or
Amortized
Cost
 
Gross
Unrealized
Gains
 
Gross
Unrealized
Losses
 
Total
Estimated
Fair Value
Cash
$
2,595

 
$
—

 
$
—

 
$
2,595

Level 1 securities:
 
 
 
 
 
 
 
Money market funds
5,561

 
—

 
—

 
5,561

Equity securities
2

 
—

 
—

 
2

Level 2 securities:
 
 
 
 
 
 
 
Foreign government and agency securities
763

 
9

 
—

 
772

U.S. government and agency securities
1,809

 
3

 
(2
)
 
1,810

Corporate debt securities
719

 
6

 
—

 
725

Asset-backed securities
49

 
—

 
—

 
49

Other fixed income securities
33

 
—

 
—

 
33

 
$
11,531

 
$
18

 
$
(2
)
 
$
11,547

Less: Restricted cash, cash equivalents, and marketable securities (1)
 
 
 
 
 
 
(99
)
Total cash, cash equivalents, and marketable securities
 
 
 
 
 
 
$
11,448

___________________
(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, and real estate lease agreements. We classify cash 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 8—Commitments and Contingencies.”

The following table summarizes gross gains and gross losses realized on sales of available-for-sale marketable securities (in millions):

 
Year Ended December 31,
 
2013
 
2012
 
2011
Realized gains
$
6

 
$
20

 
$
15

Realized losses
(7
)
 
10

 
11



The following table summarizes the contractual maturities of our cash equivalent and marketable fixed income securities as of December 31, 2013 (in millions):

 
Amortized
Cost
 
Estimated
Fair Value
Due within one year
$
7,226

 
$
7,227

Due after one year through five years
2,115

 
2,118

Due after five years through ten years
133

 
132

Due after ten years
261

 
259

 
$
9,735

 
$
9,736


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

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