NOTE 6. INVESTMENTS

The following tables summarize the Company’s available-for-sale investments at December 31, 2017 and 2016 (in thousands):



AVAILABLE-FOR-SALE INVESTMENTS
December 31, 2017
(in thousands)
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Certificates of deposit	$	13,441	$	—	$	—		$	13,441
US Treasury securities	14,787		—		(71		)	14,716
US Agency securities	8,510		—		(51		)	8,459
Commercial paper	9,171		—		—			9,171
Asset-backed securities	3,026		—		(1		)	3,025
Corporate notes and bonds	31,906		—		(70		)	31,836
Total	$	80,841	$	—	$	(193	)	$	80,648



AVAILABLE-FOR-SALE INVESTMENTS
December 31, 2016
(in thousands)
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Certificates of deposit	$	7,257	$	—	$	—		$	7,257
US Treasury securities	8,553		1		(10		)	8,544
US Agency securities	4,514		—		(13		)	4,501
Asset-backed securities	5,554		3		—			5,557
Corporate notes and bonds	32,717		3		(60		)	32,660
Total	$	58,595	$	7	$	(83	)	$	58,519

The following table summarizes the maturities of the Company’s available-for-sale securities at December 31, 2017, and 2016 (in thousands):



AVAILABLE-FOR-SALE INVESTMENT MATURITIES
(in thousands)
	At December 31, 2017				At December 31, 2016
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due in less than 1 year	$	55,801	$	55,735	$	45,391	$	45,344
Due in 1-5 years	25,040		24,913		13,204		13,175
Total	$	80,841	$	80,648	$	58,595	$	58,519

Proceeds from sales of marketable securities (including principal paydowns) for the years ended December 31, 2017, and 2016, were $11.5 million and $9.7 million, respectively. The Company determines gains and losses of marketable securities based on specific identification of the securities sold. There were no realized gains from sales of marketable securities the year ended December 31, 2017, and $6,000 gross realized gains from sales of marketable securities for year ended December 31, 2016. The gross proceeds associated with the realized gains for the year ended December 31, 2016 were $7.2 million. No material balances were reclassified out of accumulated other comprehensive income (loss) for the years ended December 31, 2017, 2016 and 2015.

No other-than-temporary impairments are recorded as no investments had a fair value that remained less than its cost for more than twelve months as of December 31, 2017, and 2016. The Company does not intend to sell investments and it is more likely than not that we will not be required to sell investments before recovering the amortized cost.

Additional information regarding the fair value of our financial instruments is included in Item 8, Note 5, Fair Value of Financial Instruments.