Investments (Tables)

9 Months Ended

Sep. 30, 2016

Investments [Abstract]

Fair value of short and long-term investments classified as available for sale

As of September 30, 2016 and December 31, 2015, the estimated fair value of our short-term and long-term investments classified as available for sale, were as follows:

	September 30, 2016
	Gross Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
	(In millions)
Short-term investments:
Restricted cash	$	24	$	—	$	—		$	24
Corporate debt securities (1)	4,763		1		(15		)	4,749
Government and agency securities	16		—		—			16
Equity instruments	9		1,494		—			1,503
	$	4,812	$	1,495	$	(15	)	$	6,292
Long-term investments:
Corporate debt securities (1)	3,738		25		(4		)	3,759
Government and agency securities	51		1		—			52
	$	3,789	$	26	$	(4	)	$	3,811

(1) As of September 30, 2016 investment securities with a fair value and a net unrealized foreign exchange loss of $1.2 billion and $15 million, respectively, were held by a foreign subsidiary in which the U.S. dollar is not the functional currency.

	December 31, 2015
	Gross Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
	(In millions)
Short-term investments:
Restricted cash	$	28	$	—	$	—		$	28
Corporate debt securities	3,302		1		(16		)	3,287
Government and agency securities	55		—		—			55
Equity instruments	9		920		—			929
	$	3,394	$	921	$	(16	)	$	4,299
Long-term investments:
Corporate debt securities	3,327		7		(67		)	3,267
	$	3,327	$	7	$	(67	)	$	3,267

Estimated fair values of short and long-term investments classified by date of contractual maturity

The estimated fair values of our short-term and long-term investments classified as available for sale by date of contractual maturity as of September 30, 2016 are as follows:  

	September 30, 2016
	(In millions)
One year or less (including restricted cash of $24)	$	4,790
One year through two years	1,492
Two years through three years	1,949
Three years through four years	115
Four years through five years	223
Five years through six years	30
Six years through seven years	1
	$	8,600