Securities (Tables)

6 Months Ended

Jun. 30, 2014

Available-for-sale Securities [Abstract]

Securities Available for Sale

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, 2014
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	862,248	$	11,858	$	(11,488	)	$	862,618
State and municipal securities	368,221		13,783		(1,498		)	380,506
U.S. government agency and government-sponsored enterprise securities	325,341		492		(4,444		)	321,389
U.S. government securities	20,895		1		(559		)	20,337
Other securities	5,284		22		(139		)	5,167
Total	$	1,581,989	$	26,156	$	(18,128	)	$	1,590,017
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

Schedule of Contractual Maturities of Investment Securities Available for Sale

The scheduled contractual maturities of investment securities available for sale at June 30, 2014 are presented as follows:

	June 30, 2014
	Amortized Cost		Fair Value
	(in thousands)
Due within one year	$	21,359	$	21,470
Due after one year through five years	332,516		333,068
Due after five years through ten years	431,423		432,434
Due after ten years	791,407		797,878
Other securities with no stated maturity	5,284		5,167
Total investment securities available-for-sale	$	1,581,989	$	1,590,017

Carrying Value of Securities Pledged As Collateral

The following table summarizes, as of June 30, 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	$	291,729
Federal Reserve Bank to secure borrowings	42,582
Other securities pledged	43,994
Total securities pledged as collateral	$	378,305

Summary of Gross Unrealized Losses and Fair Value of the Investments with Unrealized Losses

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, 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)
June 30, 2014
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	70,725	$	(160	)	$	296,832	$	(11,328	)	$	367,557	$	(11,488	)
State and municipal securities	26,340		(101		)	61,424		(1,397		)	87,764		(1,498		)
U.S. government agency and government-sponsored enterprise securities	16,231		(2		)	246,776		(4,442		)	263,007		(4,444		)
U.S. government securities	—		—			19,288		(559		)	19,288		(559		)
Other securities	—		—			5,131		(139		)	5,131		(139		)
Total	$	113,296	$	(263	)	$	629,451	$	(17,865	)	$	742,747	$	(18,128	)
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	)