3. Cash, cash equivalents and marketable securities

The following is a summary of cash, cash equivalents and marketable securities available-for-sale as of September 30, 2016 and December 31, 2015 (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
September 30, 2016
Cash and cash equivalents:
Cash	$	2,384	$	-	$	-		$	2,384
Money market funds		19,637		-		-			19,637
Corporate debt securities		1,000		-		-			1,000
Total cash and cash equivalents		23,021		-		-			23,021
Marketable securities available-for-sale:
U.S. Treasuries		6,522		4		-			6,526
U.S. Government agency securities		48,845		25		-			48,870
Corporate debt securities		31,144		5		(15	)		31,134
Total marketable securities available-for-sale		86,511		34		(15	)		86,530
Total cash, cash equivalents and marketable securities	$	109,532	$	34	$	(15	)	$	109,551
December 31, 2015
Cash and cash equivalents:
Cash	$	4,561	$	-	$	-		$	4,561
Money market funds		21,193		-		-			21,193
Corporate debt securities		19,052		7		(1	)		19,058
Total cash and cash equivalents		44,806		7		(1	)		44,812
Marketable securities available-for-sale:
U.S. Government agency securities		17,628		-		(6	)		17,622
Corporate debt securities		133,679		71		(59	)		133,691
Total marketable securities available-for-sale		151,307		71		(65	)		151,313
Total cash, cash equivalents and marketable securities	$	196,113	$	78	$	(66	)	$	196,125

The maturities of our marketable securities available-for-sale are as follows (in thousands):

	September 30, 2016
	Amortized Cost		Estimated Fair Value
Mature in one year or less	$	86,511	$	86,530
Mature after one year through two years		-		-
	$	86,511	$	86,530

We have classified our entire investment portfolio as available-for-sale and available for use in current operations and accordingly have classified all investments as short-term. Available-for-sale securities are carried at fair value, with unrealized gains and losses included in accumulated other comprehensive income (loss) in stockholders’ equity. Realized gains and losses and declines in value, if any, judged to be other than temporary on available-for-sale securities are included in interest income. The cost of securities sold is based on the specific identification method. Management assesses whether declines in the fair value of investment securities are other than temporary. In determining whether a decline is other than temporary, management considers the following factors:

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Whether the investment has been in a continuous realized loss position for over 12 months;

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the duration to maturity of our investments;

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our intention and ability to hold the investments to maturity and if it is not more likely than not that we will be required to sell the investment before recovery of the amortized cost bases;

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the credit rating, financial condition and near-term prospects of the issuer; and

•

the type of investments made.

To date, there have been no declines in fair value that have been identified as other than temporary.