3. INVESTMENT SECURITIES

The amortized cost, unrealized gains and losses and estimated fair values of investments in debt and other securities at March 31, 2017 are summarized as follows:

(in thousands)	Amortized cost		Unrealized gains		Unrealized losses			Estimated fair value

Investment securities available-for-sale:
U.S. Treasury Securities	$	28,699	$	—	$	(91	)	$	28,608
Securities of U.S. government agencies and corporations		22,376		5		(155	)		22,226
Obligations of states and political subdivisions		30,471		268		(152	)		30,587
Collateralized mortgage obligations		53,695		—		(1,013	)		52,682
Mortgage-backed securities		160,966		281		(1,907	)		159,340
Total debt securities	$	296,207	$	554	$	(3,318	)	$	293,443

The amortized cost, unrealized gains and losses and estimated fair values of investments in debt and other securities at December 31, 2016 are summarized as follows:

(in thousands)	Amortized cost		Unrealized gains		Unrealized losses			Estimated fair value

Investment securities available-for-sale:
U.S. Treasury Securities	$	28,738	$	2	$	(88	)	$	28,652
Securities of U.S. government agencies and corporations		24,382		2		(187	)		24,197
Obligations of states and political subdivisions		30,870		271		(253	)		30,888
Collateralized mortgage obligations		51,002		1		(1,065	)		49,938
Mortgage-backed securities		144,883		280		(1,759	)		143,404
Total debt securities	$	279,875	$	556	$	(3,352	)	$	277,079

The Company had $2,737,000 and $3,978,000 proceeds from sales/calls of available-for-sale securities for the three months ended March 31, 2017 and March 31, 2016, respectively. There were $0 and $14,000 gross realized gains from sales/calls of available-for-sale securities for the three months ended March 31, 2017 and March 31, 2016, respectively. There were $(16,000) and $0 gross realized losses from sales/calls of available-for-sale securities for the three months ended March 31, 2017 and March 31, 2016, respectively.

The amortized cost and estimated market value of debt and other securities at March 31, 2017, by contractual and expected maturity, are shown in the following table:

(in thousands)	Amortized cost		Estimated fair value

Maturity in years:
Due in one year or less	$	28,548	$	28,535
Due after one year through five years		45,642		45,378
Due after five years through ten years		7,356		7,508
Due after ten years		—		—
Subtotal		81,546		81,421
MBS & CMO		214,661		212,022
Total		296,207		293,443

Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. In addition, factors such as prepayments and interest rates may affect the yield on the carrying value of mortgage-related securities.

An analysis of gross unrealized losses of the available-for-sale investment securities portfolio as of March 31, 2017, follows:

	Less than 12 months					12 months or more					Total
(in thousands)	Fair Value		Unrealized losses			Fair Value		Unrealized losses			Fair Value		Unrealized losses

U.S. Treasury securities	$	28,608	$	(91	)	$	—	$	—		$	28,608	$	(91	)
Securities of U.S. government agencies and corporations		19,221		(155	)		—		—			19,221		(155	)
Obligations of states and political subdivisions		15,971		(147	)		996		(5	)		16,967		(152	)
Collateralized Mortgage obligations		47,541		(1,013	)		—		—			47,541		(1,013	)
Mortgage-backed securities		126,384		(1,829	)		6,304		(78	)		132,688		(1,907	)
Total	$	237,725	$	(3,235	)	$	7,300	$	(83	)	$	245,025	$	(3,318	)

No decline in value was considered "other-than-temporary" during the first three months of 2017. One hundred sixty four securities, all considered investment grade, which had a fair value of $237,725,000 and a total unrealized loss of $3,235,000 have been in an unrealized loss position for less than twelve months as of March 31, 2017. Thirteen securities, all considered investment grade, which had a fair value of $7,300,000 and a total unrealized loss of $83,000 have been in an unrealized loss position for more than twelve months as of March 31, 2017. The declines in fair value were attributable to changes in interest rates. We have evaluated the credit ratings of our investment securities and their issuer and/or insurers, and based on this evaluation have determined that no investment security in our investment portfolio was other-than-temporarily impaired as of March 31, 2017. As the Company does not intend to sell these securities and it is not more likely than not that the Company will be required to sell these securities prior to their anticipated recovery, these investments are not considered other-than-temporarily impaired.

An analysis of gross unrealized losses of the available-for-sale investment securities portfolio as of December 31, 2016, follows:

	Less than 12 months					12 months or more					Total
(in thousands)	Fair Value		Unrealized losses			Fair Value		Unrealized losses			Fair Value		Unrealized losses

U.S. Treasury Securities	$	23,564	$	(88	)	$	—	$	—		$	23,564	$	(88	)
Securities of U.S. government agencies and corporations		22,195		(187	)		—		—			22,195		(187	)
Obligations of states and political subdivisions		16,168		(245	)		996		(8	)		17,164		(253	)
Collateralized Mortgage obligations		49,805		(1,065	)		—		—			49,805		(1,065	)
Mortgage-backed securities		109,092		(1,678	)		4,829		(81	)		113,921		(1,759	)
Total	$	220,824	$	(3,263	)	$	5,825	$	(89	)	$	226,649	$	(3,352	)

Investment securities carried at $36,473,000 and $38,152,000 at March 31, 2017 and December 31, 2016, respectively, were pledged to secure public deposits or for other purposes as required or permitted by law.