Available-for-Sale Debt Securities

6 Months Ended

Jun. 30, 2020

Debt Securities, Available-for-sale [Abstract]

Available-for-Sale Debt securities

AVAILABLE-FOR-SALE DEBT SECURITIES

The following table summarizes our available-for-sale debt securities (in millions):

	June 30, 2020								December 31, 2019
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
U.S. treasury securities	$	2,479	$	19	$	—	$	2,498	$	2,433	$	—	$	—	$	2,433
Certificates of deposit	2,783		—		—		2,783		3,517		—		—		3,517
U.S. government agencies securities	101		—		—		101		1,081		—		—		1,081
Non-U.S. government securities	145		—		—		145		174		—		—		174
Corporate debt securities	8,755		31		(2)		8,784		9,203		2		(1)		9,204
Residential mortgage and asset-backed securities	621		3		—		624		91		—		—		91
Total	$	14,884	$	53	$	(2)	$	14,935	$	16,499	$	2	$	(1)	$	16,500

The following table summarizes the classification of our available-for-sale debt securities in our Condensed Consolidated Balance Sheets (in millions):

	June 30, 2020		December 31, 2019
Cash and cash equivalents	$	491	$	2,291
Short-term marketable securities	12,168		12,721
Long-term marketable securities	2,276		1,488
Total	$	14,935	$	16,500

Accrued interest receivable excluded from both the fair value and amortized cost basis of the available-for-sale debt securities was $56 million and $37 million as of June 30, 2020 and December 31, 2019, respectively, and is recorded in Prepaid and other current assets on our Condensed Consolidated Balance Sheets. In connection with the adoption of Topic 326, we made an accounting policy election to not measure an allowance for credit losses for accrued interest receivable. There were no write-offs of accrued interest receivable during the three and six months ended June 30, 2020.

The following table summarizes our available-for-sale debt securities by contractual maturity (in millions):

	June 30, 2020
	Amortized Cost		Fair Value
Within one year	$	12,623	$	12,659
After one year through five years	2,197		2,212
After five years	64		64
Total	$	14,884	$	14,935

The following table summarizes our available-for-sale debt securities in an unrealized loss position (in millions):

	Less Than 12 Months				12 Months or Greater				Total
	Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value
June 30, 2020
Corporate debt securities	$	(2)	$	1,175	$	—	$	—	$	(2)	$	1,175
December 31, 2019
Corporate debt securities	$	(1)	$	1,866	$	—	$	4	$	(1)	$	1,870

We held a total of 181 positions which were in an unrealized loss position as of June 30, 2020. The unrealized losses are largely due to changes in interest rates. We do not intend to sell these securities nor do we believe that we will be required to sell these securities before the recovery of the amortized cost basis. Accordingly, no credit losses were recognized for the three and six months ended June 30, 2020.