Securities

The following tables present the amortized cost, gross unrealized holding gains, gross unrealized holding losses and fair value of securities by major security type and class of security:



(Dollars in thousands)
March 31, 2016	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Securities Available for Sale:
Obligations of U.S. government-sponsored enterprises		$97,151		$160		($26	)		$97,285
Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises	249,141		8,322		—			257,463
Obligations of states and political subdivisions	31,025		511		—			31,536
Individual name issuer trust preferred debt securities	29,824		—		(6,743		)	23,081
Corporate bonds	1,965		32		(10		)	1,987
Total securities available for sale		$409,106		$9,025		($6,779	)		$411,352
Held to Maturity:
Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises		$19,040		$624		$—			$19,664
Total securities held to maturity		$19,040		$624		$—			$19,664
Total securities		$428,146		$9,649		($6,779	)		$431,016



(Dollars in thousands)
December 31, 2015	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Securities Available for Sale:
Obligations of U.S. government-sponsored enterprises		$77,330		$73		($388	)		$77,015
Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises	228,908		6,398		(450		)	234,856
Obligations of states and political subdivisions	35,353		727		—			36,080
Individual name issuer trust preferred debt securities	29,815		—		(4,677		)	25,138
Corporate bonds	1,970		5		(20		)	1,955
Total securities available for sale		$373,376		$7,203		($5,535	)		$375,044
Held to Maturity:
Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises		$20,023		$493		$—			$20,516
Total securities held to maturity		$20,023		$493		$—			$20,516
Total securities		$393,399		$7,696		($5,535	)		$395,560

At March 31, 2016 and December 31, 2015, securities available for sale and held to maturity with a fair value of $357.5 million and $346.1 million, respectively, were pledged as collateral for Federal Home Loan Bank of Boston (“FHLBB”) borrowings, potential borrowings with the FRB, certain public deposits and for other purposes. See Note 7 for additional disclosure on FHLBB borrowings.

The schedule of maturities of debt securities available for sale and held to maturity is presented below. Mortgage-backed securities are included based on weighted average maturities, adjusted for anticipated prepayments. All other debt securities are included based on contractual maturities. Actual maturities may differ from amounts presented because certain issuers have the right to call or prepay obligations with or without call or prepayment penalties.



(Dollars in thousands)	Available for Sale				Held to Maturity
March 31, 2016	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due in one year or less		$42,724		$44,084		$2,473		$2,554
Due after one year to five years	143,155		147,073		7,650		7,901
Due after five years to ten years	157,073		159,571		5,978		6,174
Due after ten years	66,154		60,624		2,939		3,035
Total securities		$409,106		$411,352		$19,040		$19,664

Included in the above table are debt securities with an amortized cost balance of $155.0 million and a fair value of $148.9 million at March 31, 2016 that are callable at the discretion of the issuers. Final maturities of the callable securities range from 11 months to 21 years, with call features ranging from 1 month to 5 years.

Other-Than-Temporary Impairment Assessment

Washington Trust assesses whether the decline in fair value of investment securities is other-than-temporary on a regular basis. Unrealized losses on debt securities may occur from current market conditions, increases in interest rates since the time of purchase, a structural change in an investment, volatility of earnings of a specific issuer, or deterioration in credit quality of the issuer. Management evaluates impairments in value both qualitatively and quantitatively to assess whether they are other-than-temporary.

The following tables summarize temporarily impaired securities, segregated by length of time the securities have been in a continuous unrealized loss position:



(Dollars in thousands)	Less than 12 Months						12 Months or Longer						Total
March 31, 2016	#	Fair Value		Unrealized Losses			#	Fair Value		Unrealized Losses			#	Fair Value		Unrealized Losses
Obligations of U.S. government-sponsored enterprises	1		$9,974		($26	)	—		$—		$—		1		$9,974		($26	)
Individual name issuer trust preferred debt securities	—	—		—			10	23,081		(6,743		)	10	23,081		(6,743		)
Corporate bonds	1	491		(10		)	—	—		—			1	491		(10		)
Total temporarily impaired securities	2		$10,465		($36	)	10		$23,081		($6,743	)	12		$33,546		($6,779	)



(Dollars in thousands)	Less than 12 Months						12 Months or Longer						Total
December 31, 2015	#	Fair Value		Unrealized Losses			#	Fair Value		Unrealized Losses			#	Fair Value		Unrealized Losses
Obligations of U.S. government-sponsored enterprises	4		$34,767		($388	)	—		$—		$—		4		$34,767		($388	)
Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises	9	61,764		(450		)	—	—		—			9	61,764		(450		)
Individual name issuer trust preferred debt securities	—	—		—			10	25,138		(4,677		)	10	25,138		(4,677		)
Corporate bonds	3	1,235		(20		)	—	—		—			3	1,235		(20		)
Total temporarily impaired securities	16		$97,766		($858	)	10		$25,138		($4,677	)	26		$122,904		($5,535	)

Further deterioration in credit quality of the underlying issuers of the securities, further deterioration in the condition of the financial services industry, a continuation or worsening of the current economic environment, or additional declines in real estate values, among other things, may further affect the fair value of these securities and increase the potential that certain unrealized losses be designated as other-than-temporary in future periods, and the Corporation may incur write-downs.

Unrealized losses on temporarily impaired securities as of March 31, 2016 and December 31, 2015 were concentrated in variable rate trust preferred debt securities.

Trust Preferred Debt Securities of Individual Name Issuers

Included in debt securities in an unrealized loss position at March 31, 2016 were 10 trust preferred security holdings issued by 7 individual companies in the banking sector. Management believes the unrealized loss position in these holdings was attributable to the general widening of spreads for this category of debt securities issued by financial services companies since the time these securities were purchased. Based on the information available through the filing date of this report, all individual name issuer trust preferred debt securities held in our portfolio continue to accrue and make payments as expected with no payment deferrals or defaults on the part of the issuers. As of March 31, 2016, individual name issuer trust preferred debt securities with an amortized cost of $10.9 million and unrealized losses of $2.4 million were rated below investment grade by Standard & Poors, Inc. (“S&P”). Management reviewed the collectibility of these securities taking into consideration such factors as the financial condition of the issuers, reported regulatory capital ratios of the issuers, credit ratings, including ratings in effect as of the reporting period date as well as credit rating changes between the reporting period date and the filing date of this report, and other information. We noted no additional downgrades to below investment grade between December 31, 2015 and the filing date of this report. Based on these analyses, management concluded that it expects to recover the entire amortized cost basis of these securities. Furthermore, Washington Trust does not intend to sell these securities and it is not more‑likely‑than‑not that Washington Trust will be required to sell these securities before recovery of their cost basis, which may be maturity. Therefore, management does not consider these investments to be other-than-temporarily impaired at March 31, 2016.