. Marketable Securities

The Company has classified its marketable securities as available-for-sale securities. These securities are carried at estimated fair value with unrealized holding gains and losses included in accumulated other comprehensive income (loss) in stockholders’ equity until realized. Gains and losses on marketable security transactions are reported on the specific-identification method. Dividend and interest income are recognized when earned.

The amortized cost, gross unrealized holding gains, gross unrealized holding losses, and fair value for available-for-sale securities by major security type and class of securities at

March 31, 2018

and

December 31, 2017

were as follows:

	Amortized cost		Gross unrealized holding gains		Gross unrealized holding losses			Estimated fair value
March 31, 2018
Available-for-sale securities:
Corporate bonds and notes	$	6,040	$	5	$	(73	)	$	5,972
Municipal bonds		4,613		0		(37	)		4,576
Total available-for-sale securities	$	10,653	$	5	$	(110	)	$	10,548

	Amortized cost		Gross unrealized holding gains		Gross unrealized holding losses			Estimated fair value
December 31, 201 7
Available-for-sale securities:
Corporate bonds and notes	$	8,458	$	19	$	(49	)	$	8,428
Municipal bonds		4,637		1		(28	)		4,610
Total available-for-sale securities	$	13,095	$	20	$	(77	)	$	13,038

Maturities of marketable securities classified as available-for-sale securities were as follows at

March 31, 2018:

	Amortized cost		Estimated fair value
March 31, 2018
Due within one year	$	3,145	$	3,132
Due after one year through five years		7,508		7,416
Total available-for-sale securities	$	10,653	$	10,548

Debt securities in an unrealized loss position as of

March 31, 2018

were

not

deemed impaired at acquisition and subsequent declines in fair value are

not

deemed attributed to declines in credit quality. Management believes that it is more likely than

not

that the securities will receive a full recovery of par value, although there can be

assurance that such recovery will occur. The available-for-sale marketable securities with continuous gross unrealized loss position for less than

months and

months or greater and their related fair values were as follows:

	Less than 12 months					More than 12 months					Total
(In thousands)	Estimated fair value		Gross unrealized holding losses			Estimated fair value		Gross unrealized holding losses			Estimated fair value		Gross unrealized holding losses
As of March 31, 2018
Corporate bonds and notes	$	3,106	$	(30	)	$	2,282	$	(43	)	$	5,388	$	(73	)
Municipal bonds		3,197		(28	)		670		(9	)		3,867		(37	)
Total	$	6,303	$	(58	)	$	2,952	$	(52	)	$	9,255	$	(110	)