Securities

The following table summarizes the amortized cost, gross unrealized gains and losses and the resulting fair value of securities available for sale:



	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
March 31, 2014
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	919,299	$	10,339	$	(17,340	)	$	912,298
State and municipal securities	363,983		12,472		(2,775		)	373,680
U.S. government agency and government-sponsored enterprise securities	335,151		477		(7,642		)	327,986
U.S. government securities	21,088		1		(786		)	20,303
Other securities	5,284		25		(206		)	5,103
Total	$	1,644,805	$	23,314	$	(28,749	)	$	1,639,370
December 31, 2013
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	961,442	$	10,640	$	(23,674	)	$	948,408
State and municipal securities	357,013		11,450		(3,993		)	364,470
U.S. government agency and government-sponsored enterprise securities	335,671		434		(10,066		)	326,039
U.S. government securities	21,081		—		(967		)	20,114
Other securities	5,284		27		(231		)	5,080
Total	$	1,680,491	$	22,551	$	(38,931	)	$	1,664,111

The scheduled contractual maturities of investment securities available for sale at March 31, 2014 are presented as follows:



	March 31, 2014
	Amortized Cost		Fair Value
	(in thousands)
Due within one year	$	23,252	$	23,415
Due after one year through five years	337,507		336,477
Due after five years through ten years	434,217		431,506
Due after ten years	844,545		842,869
Other securities with no stated maturity	5,284		5,103
Total investment securities available-for-sale	$	1,644,805	$	1,639,370

The following table summarizes, as of March 31, 2014, the carrying value of securities pledged as collateral to secure public deposits, borrowings and other purposes as permitted or required by law:



	Carrying Amount
	(in thousands)
Washington and Oregon State to secure public deposits	$	278,061
Federal Reserve Bank to secure borrowings	42,631
Other securities pledged	43,038
Total securities pledged as collateral	$	363,730

The following table shows the gross unrealized losses and fair value of the Company’s investments with unrealized losses that are not deemed to be other-than-temporarily impaired, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at March 31, 2014 and December 31, 2013:




	Less than 12 Months					12 Months or More					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(in thousands)
March 31, 2014
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	399,830	$	(7,290	)	$	112,690	$	(10,050	)	$	512,520	$	(17,340	)
State and municipal securities	88,065		(1,791		)	17,748		(984		)	105,813		(2,775		)
U.S. government agency and government-sponsored enterprise securities	251,196		(6,026		)	28,810		(1,616		)	280,006		(7,642		)
U.S. government securities	19,253		(786		)	—		—			19,253		(786		)
Other securities	2,270		(45		)	2,795		(161		)	5,065		(206		)
Total	$	760,614	$	(15,938	)	$	162,043	$	(12,811	)	$	922,657	$	(28,749	)

December 31, 2013
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	492,921	$	(10,991	)	$	121,303	$	(12,684	)	$	614,224	$	(23,675	)
State and municipal securities	112,400		(3,069		)	13,815		(923		)	126,215		(3,992		)
U.S. government agency and government-sponsored enterprise securities	260,001		(8,063		)	28,447		(2,003		)	288,448		(10,066		)
U.S. government securities	20,114		(967		)	—		—			20,114		(967		)
Other securities	2,257		(58		)	2,783		(173		)	5,040		(231		)
Total	$	887,693	$	(23,148	)	$	166,348	$	(15,783	)	$	1,054,041	$	(38,931	)

At March 31, 2014, there were 70 U.S. government agency and government-sponsored enterprise mortgage-backed securities & collateralized mortgage obligations securities in an unrealized loss position, of which ten were in a continuous loss position for 12 months or more. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company does not consider these investments to be other-than-temporarily impaired at March 31, 2014.

At March 31, 2014, there were 113 state and municipal government securities in an unrealized loss position, of which 13 were in a continuous loss position for 12 months or more. The unrealized losses on state and municipal securities were caused by interest rate changes or widening of market spreads subsequent to the purchase of the individual securities. Management monitors published credit ratings of these securities for adverse changes. As of March 31, 2014, none of the rated obligations of state and local government entities held by the Company had a below investment grade credit rating. Because the credit quality of these securities are investment grade and the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company does not consider these investments to be other-than-temporarily impaired at March 31, 2014.

At March 31, 2014, there were 29 U.S. government agency and government-sponsored enterprise securities in an unrealized loss position, three of which were in a continuous loss position for 12 months or more. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not currently intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be maturity, the Company does not consider these investments to be other-than-temporarily impaired at March 31, 2014.

At March 31, 2014, there were three U.S. government securities in an unrealized loss position, none of which were in a continuous loss position for 12 months or more. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not currently intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be maturity, the Company does not consider these investments to be other-than-temporarily impaired at March 31, 2014.

At March 31, 2014, there were two other securities in an unrealized loss position, of which one security, a mortgage-backed securities fund, was in a continuous unrealized loss position for 12 months or more. The decline in fair value is attributable to changes in interest rates and the additional risk premium investors are demanding for investment securities with these characteristics. The Company does not consider this investment to be other-than-temporarily impaired at March 31, 2014 as it has the intent and ability to hold the investment for sufficient time to allow for recovery in the market value.