Investment Securities

The carrying values and estimated fair values of investment securities at the periods indicated are presented below:



(In Thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
March 31, 2017
Securities available for sale
U.S. Treasury and government sponsored entities		$261,283		$142		$790		$260,635
Municipal securities	18,001		95		28		18,068
U.S. Agency mortgage-backed securities	1		—		—		1
Corporate bonds	39,442		414		—		39,856
Preferred stock	5,421		162		5		5,578
Total securities available for sale		$324,148		$813		$823		$324,138
Securities held to maturity
Municipal securities		$899		$15		$—		$914
Total securities held to maturity		$899		$15		$—		$914
December 31, 2016
Securities available for sale
U.S. Treasury and government sponsored entities		$264,267		$150		$1,056		$263,361
Municipal securities	18,184		26		53		18,157
U.S. Agency mortgage-backed securities	2		—		—		2
Corporate bonds	44,437		295		—		44,732
Preferred stock	4,922		49		4		4,967
Total securities available for sale		$331,812		$520		$1,113		$331,219
Securities held to maturity
Municipal securities		$899		$23		$—		$922
Total securities held to maturity		$899		$23		$—		$922

Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at March 31, 2017 and December 31, 2016 were as follows:



	Less Than 12 Months				More Than 12 Months				Total
(In Thousands)	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
March 31, 2017:
Securities Available for Sale
U.S. Treasury and government sponsored entities		$172,627		$784		$489		$6		$173,116		$790
Municipal Securities	4,234		9		1,784		19		6,018		28
Preferred Stock	—		—		1,036		5		1,036		5
Total		$176,861		$793		$3,309		$30		$180,170		$823

December 31, 2016:
Securities Available for Sale
U.S. Treasury and government sponsored entities		$180,638		$1,051		$489		$5		$181,127		$1,056
Municipal Securities	11,533		33		1,786		20		13,319		53
Preferred Stock	—		—		1,038		4		1,038		4
Total		$192,171		$1,084		$3,313		$29		$195,484		$1,113

The unrealized losses on investments in U.S. treasury and government sponsored entities, preferred stock, and municipal securities in both periods were caused by changes in interest rates. At March 31, 2017 and December 31, 2016, respectively, there were twenty-six and thirty-four available-for-sale securities with unrealized losses that have been in a loss position for less than twelve months. There were four securities as of March 31, 2017 and December 31, 2016 that have been in an unrealized loss position for more than twelve months. The contractual terms of the investments in a loss position do not permit the issuer to settle the securities at a price less than the amortized cost of the investment. Because it is more likely than not that the Company will hold these investments until a market price recovery or maturity, these investments are not considered other-than-temporarily impaired.

At March 31, 2017 and December 31, 2016, $51.2 million and $50.9 million in securities were pledged for deposits and borrowings.

The amortized cost and estimated fair values of debt securities at March 31, 2017, are distributed by contractual maturity as shown below. Expected maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Although preferred stock has no stated maturity, it is aggregated in the calculation of weighted average yields presented below in the category of investments that mature in ten years or more.



(In Thousands)	Amortized Cost		Fair Value		Weighted Average Yield
US Treasury and government sponsored entities
Within 1 year		$37,002		$36,997	0.97	%
1-5 years	224,281		223,638		6.57	%
Total		$261,283		$260,635	5.78	%
U.S. Agency mortgage-backed securities
1-5 years		$1		$1	5.06	%
Total		$1		$1	5.06	%
Corporate bonds
Within 1 year		$4,801		$4,807	1.40	%
1-5 years	26,206		26,443		1.88	%
5-10 years	8,435		8,606		2.32	%
Total		$39,442		$39,856	1.92	%
Preferred stock
Over 10 years		$5,421		$5,578	6.37	%
Total		$5,421		$5,578	6.37	%
Municipal securities
Within 1 year		$3,421		$3,420	1.49	%
1-5 years	13,988		14,083		2.27	%
5-10 years	1,491		1,479		4.78	%
Total		$18,900		$18,982	2.33	%

The proceeds and resulting gains and losses, computed using specific identification, from sales of investment securities for the three months ending March 31, 2017 and 2016, respectively, are as follows:



(In Thousands)	Proceeds		Gross Gains		Gross Losses
2017
Available for sale securities		$10,010		$14		$—
2016
Available for sale securities		$771		$—		$23

A summary of interest income for the three months ending March 31, 2017 and 2016, on available for sale investment securities is as follows:



(In Thousands)	2017		2016
US Treasury and government sponsored entities		$778		$679
U.S. Agency mortgage-backed securities	—		4
Other	289		222
Total taxable interest income		$1,067		$905
Municipal securities		$97		$75
Total tax-exempt interest income		$97		$75
Total		$1,164		$980