

	March 31, 2019		December 31, 2018
	(in millions)
Short-term investments:
Equity investment securities	$	25	$	25
Available-for-sale investment securities	1,361		1,760
Held-to-maturity investment securities	826		1,065
Time deposits ⁽¹⁾	506		500
Total short-term investments	$	2,718	$	3,350



Long-term investments:
Equity and cost method investments	$	73	$	74
Held-to-maturity investment securities	6		6
Total long-term investments	$	79	$	80

Our equity investment securities consist of a U.S. dollar denominated investment in a fixed income mutual fund. For the three months ended March 31, 2019 and 2018, realized and unrealized gains and losses were immaterial. The value of the fixed income mutual fund is based on the net asset value ("NAV") of the fund, with appropriate consideration of the liquidity and any restrictions on disposition of our investment in the fund.

Our available-for-sale investment securities consist of U.S. dollar denominated investments primarily in U.S. Treasury notes, U.S. government agency debt securities, municipal debt securities, non-U.S. government debt securities, U.S. and international corporate bonds, certificates of deposit, commercial paper, debt securities issued by supranational institutions, and asset-backed securities, including securities backed by auto loans, credit card receivables, and other receivables. Our investment guidelines are to purchase securities which are investment grade at the time of acquisition. We monitor the credit ratings of the securities in our portfolio on an ongoing basis.

The amortized cost, gross unrealized gains and losses and fair value of available-for-sale investment securities at March 31, 2019 were as follows:



	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
	(in millions)
U.S. Treasury and agency debt securities	$	576	$	1	$	(4	)	$	573
Corporate and other debt securities	371		1		(1		)	371
Certificates of deposit and commercial paper	19		—		—			19
Asset-backed securities	341		1		(1		)	341
Municipal debt securities	57		—		—			57
Total available-for-sale investment securities	$	1,364	$	3	$	(6	)	$	1,361

The amortized cost, gross unrealized gains and losses and fair value of available-for-sale investment securities at December 31, 2018 were as follows:



	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
	(in millions)
U.S. Treasury and agency debt securities	$	630	$	1	$	(6	)	$	625
Corporate and other debt securities	420		—		(4		)	416
Certificates of deposit and commercial paper	296		—		—			296
Asset-backed securities	336		—		(2		)	334
Municipal debt securities	90		—		(1		)	89
Total available-for-sale investment securities	$	1,772	$	1	$	(13	)	$	1,760

The fair value and related unrealized losses of available-for-sale investment securities in a continuous unrealized loss position for less than 12 months and for 12 months or longer were as follows as of March 31, 2019:



	Less than 12 Months				12 Months or More					Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(in millions)
U.S. Treasury and agency debt securities	$	13	$	—	$	412	$	(4	)	425		(4		)
Corporate and other debt securities	15		—		233		(1		)	248		(1		)
Certificates of deposit and commercial paper	8		—		—		—			8		—
Asset-backed securities	33		—		157		(1		)	190		(1		)
Municipal debt securities	1		—		32		—			33		—
Total	$	70	$	—	$	834	$	(6	)	$	904	$	(6	)



	Less than 12 Months					12 Months or More					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(in millions)
U.S. Treasury and agency debt securities	$	84	$	—		$	446	$	(6	)	$	530	$	(6	)
Corporate and other debt securities	108		(1		)	254		(3		)	362		(4		)
Certificates of deposit and commercial paper	295		—			—		—			295		—
Asset-backed securities	93		—			179		(2		)	272		(2		)
Municipal debt securities	17		—			64		(1		)	81		(1		)
Total	$	597	$	(1	)	$	943	$	(12	)	$	1,540	$	(13	)

The unrealized losses for the above securities as of March 31, 2019 and December 31, 2018 were primarily attributable to changes in interest rates. At each reporting date, we perform an evaluation of impaired available-for-sale securities to determine if the unrealized losses are other-than-temporary. We do not consider any of the investments to be other-than-temporarily impaired as of March 31, 2019. The gross unrealized gains and losses in the above tables were recorded, net of tax, in "Accumulated other comprehensive income (loss)" in our unaudited consolidated statements of financial position.

The contractual maturities of our fixed income available-for-sale investment securities as of March 31, 2019 are set forth in the following table:



	Amortized Cost		Fair Value
	(in millions)
Due within one year	$	299	$	297
Due after one year up to two years	485		482
Due after two years up to three years	179		180
Due after three years	60		61
Asset-backed securities	341		341
Total available-for-sale investment securities	$	1,364	$	1,361

Asset-backed securities were excluded from the maturity categories because the actual maturities may differ from the contractual maturities since the underlying receivables may be prepaid without penalties. Further, actual maturities of debt securities may differ from those presented above since certain obligations provide the issuer the right to call or prepay the obligation prior to scheduled maturity without penalty.

Proceeds from sales of available-for-sale investment securities and the gross gains and losses that have been included in earnings as a result of those sales were as follows:



	Three Months Ended March 31,
	2019			2018
	(in millions)
Proceeds from sales of available-for-sale investment securities	$	314		$	125

Gross gains	$	1		$	—
Gross losses	(1		)	(1		)
Net realized (losses) on sales of available-for-sale investment securities	$	—		$	(1	)

Our held-to-maturity investment securities consist of Indian rupee denominated investments primarily in commercial paper, international corporate bonds and government debt securities. Our investment guidelines are to purchase securities that are investment grade at the time of acquisition. We monitor the credit ratings of the securities in our portfolio on an ongoing basis.

The amortized cost, gross unrealized gains and losses and fair value of held-to-maturity investment securities at March 31, 2019 were as follows:



	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
	(in millions)
Short-term investments:
Corporate and other debt securities	$	417	$	1	$	—	$	418
Commercial paper	409		1		—		410
Total short-term held-to-maturity investments	826		2		—		828
Long-term investments:
Corporate and other debt securities	6		—		—		6
Total held-to-maturity investment securities	$	832	$	2	$	—	$	834

The amortized cost, gross unrealized gains and losses and fair value of held-to-maturity investment securities at December 31, 2018 were as follows:



	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
	(in millions)
Short-term investments:
Corporate and other debt securities	$	546	$	—	$	—		$	546
Commercial paper	519		—		(1		)	518
Total short-term held-to-maturity investments	1,065		—		(1		)	1,064
Long-term investments:
Corporate and other debt securities	6		—		—			6
Total held-to-maturity investment securities	$	1,071	$	—	$	(1	)	$	1,070

The fair value and related unrealized losses of held-to-maturity investment securities in a continuous unrealized loss position for less than 12 months and for 12 months or longer were as follows as of March 31, 2019:



	Less than 12 Months				12 Months or More				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
	(in millions)
Corporate and other debt securities	$	29	$	—	$	6	$	—	$	35	$	—
Commercial paper	92		—		—		—		92		—
Total	$	121	$	—	$	6	$	—	$	127	$	—



	Less than 12 Months					12 Months or More				Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
	(in millions)
Corporate and other debt securities	$	263	$	—		$	57	$	—	$	320	$	—
Commercial paper	268		(1		)	—		—		268		(1		)
Total	$	531	$	(1	)	$	57	$	—	$	588	$	(1	)

At each reporting date, the Company performs an evaluation of held-to-maturity securities to determine if the unrealized losses are other-than-temporary. We do not consider any of the investments to be other-than-temporarily impaired as of March 31, 2019.

The contractual maturities of our fixed income held-to-maturity investment securities as of March 31, 2019 are set forth in the following table:



	Amortized Cost		Fair Value
	(in millions)
Due within one year	$	826	$	828
Due after one year up to two years	6		6
Total held-to-maturity investment securities	$	832	$	834