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)
June 30, 2017
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	1,438,875	$	3,478	$	(18,395	)	$	1,423,958
State and municipal securities	476,510		9,279		(2,696		)	483,093
U.S. government agency and government-sponsored enterprise securities	352,039		1,486		(1,287		)	352,238
U.S. government securities	251		—		(1		)	250
Other securities	5,284		70		(257		)	5,097
Total	$	2,272,959	$	14,313	$	(22,636	)	$	2,264,636
December 31, 2016
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	1,486,690	$	2,760	$	(23,718	)	$	1,465,732
State and municipal securities	473,914		6,343		(5,197		)	475,060
U.S. government agency and government-sponsored enterprise securities	332,348		1,065		(1,511		)	331,902
U.S. government securities	801		—		(1		)	800
Other securities	5,284		63		(264		)	5,083
Total	$	2,299,037	$	10,231	$	(30,691	)	$	2,278,577

The following table provides the proceeds and gross realized gains and losses on the sales of securities for the periods indicated:



	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2017		2016		2017		2016
	(in thousands)
Proceeds from sales of available for sale securities	$	—	$	44,534	$	—	$	83,410

Gross realized gains	$	—	$	229	$	—	$	602
Gross realized losses	—		—		—		—
Net realized gains	$	—	$	229	$	—	$	602

The scheduled contractual maturities of investment securities available for sale at June 30, 2017 are presented as follows:



	June 30, 2017
	Amortized Cost		Fair Value
	(in thousands)
Due within one year	$	99,775	$	99,740
Due after one year through five years	461,043		464,716
Due after five years through ten years	726,133		724,520
Due after ten years	980,724		970,563
Other securities with no stated maturity	5,284		5,097
Total investment securities available-for-sale	$	2,272,959	$	2,264,636

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



	June 30, 2017
	(in thousands)
Washington and Oregon State to secure public deposits	$	244,580
Federal Reserve Bank to secure borrowings	54,877
Other securities pledged	122,932
Total securities pledged as collateral	$	422,389

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 June 30, 2017 and December 31, 2016:



	Less than 12 Months					12 Months or More					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(in thousands)
June 30, 2017
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	858,558	$	(12,683	)	$	180,212	$	(5,712	)	$	1,038,770	$	(18,395	)
State and municipal securities	108,038		(2,189		)	13,246		(507		)	121,284		(2,696		)
U.S. government agency and government-sponsored enterprise securities	194,738		(1,287		)	—		—			194,738		(1,287		)
U.S. government securities	251		(1		)	—		—			251		(1		)
Other securities	2,276		(39		)	2,737		(218		)	5,013		(257		)
Total	$	1,163,861	$	(16,199	)	$	196,195	$	(6,437	)	$	1,360,056	$	(22,636	)

December 31, 2016
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	1,029,116	$	(18,788	)	$	159,046	$	(4,930	)	$	1,188,162	$	(23,718	)
State and municipal securities	211,342		(5,064		)	3,384		(133		)	214,726		(5,197		)
U.S. government agency and government-sponsored enterprise securities	218,811		(1,511		)	—		—			218,811		(1,511		)
U.S. government securities	251		(1		)	—		—			251		(1		)
Other securities	2,263		(51		)	2,743		(213		)	5,006		(264		)
Total	$	1,461,783	$	(25,415	)	$	165,173	$	(5,276	)	$	1,626,956	$	(30,691	)

At June 30, 2017, there were 172 U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations securities in an unrealized loss position, of which 54 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 June 30, 2017.

At June 30, 2017, there were 99 state and municipal government securities in an unrealized loss position, of which 11 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 June 30, 2017, 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 June 30, 2017.

At June 30, 2017, there were 22 U.S. government agency and government-sponsored enterprise securities in an unrealized loss position, of which none 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 upon maturity, the Company does not consider these investments to be other-than-temporarily impaired at June 30, 2017.

At June 30, 2017, there was one U.S. government security in an unrealized loss position, which was not 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 this investment falls within the yield curve and its individual characteristics. Because the Company does not currently intend to sell this security nor does the Company consider it more likely than not that it will be required to sell this security before the recovery of amortized cost basis, which may be upon maturity, the Company does not consider this investment to be other-than-temporarily impaired at June 30, 2017.

At June 30, 2017, there were two other securities in an unrealized loss position, of which one 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 these investments to be other-than-temporarily impaired at June 30, 2017 as it has the intent and ability to hold these investments for sufficient time to allow for recovery in the market value.