Securities (Tables)

6 Months Ended

Jun. 30, 2015

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, 2015
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	1,042,134	$	8,427	$	(9,482	)	$	1,041,079
State and municipal securities	479,847		11,184		(2,000		)	489,031
U.S. government agency and government-sponsored enterprise securities	359,714		1,195		(1,884		)	359,025
U.S. government securities	20,424		—		(262		)	20,162
Other securities	5,284		23		(159		)	5,148
Total	$	1,907,403	$	20,829	$	(13,787	)	$	1,914,445
December 31, 2014
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	1,160,378	$	10,219	$	(8,210	)	$	1,162,387
State and municipal securities	483,578		14,432		(1,526		)	496,484
U.S. government agency and government-sponsored enterprise securities	416,919		856		(4,069		)	413,706
U.S. government securities	20,910		—		(411		)	20,499
Other securities	5,284		20		(123		)	5,181
Total	$	2,087,069	$	25,527	$	(14,339	)	$	2,098,257

Schedule of gross realized gains and losses on sales and calls of securities available for sale

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

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2015		2014		2015			2014
	(in thousands)
Gross realized gains	$	343	$	296	$	1,073		$	519
Gross realized losses	—		—		(9		)	—
Net realized gains	$	343	$	296	$	1,064		$	519

Schedule of Contractual Maturities of Investment Securities Available for Sale

The scheduled contractual maturities of investment securities available for sale at June 30, 2015 are presented as follows:

	June 30, 2015
	Amortized Cost		Fair Value
	(in thousands)
Due within one year	$	20,112	$	20,399
Due after one year through five years	391,397		392,321
Due after five years through ten years	535,833		539,403
Due after ten years	954,777		957,174
Other securities with no stated maturity	5,284		5,148
Total investment securities available-for-sale	$	1,907,403	$	1,914,445

Carrying Value of Securities Pledged As Collateral

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, 2015
	(in thousands)
Washington and Oregon State to secure public deposits	$	331,431
Federal Reserve Bank to secure borrowings	55,508
Other securities pledged	149,327
Total securities pledged as collateral	$	536,266

The following table presents the class of collateral pledged for repurchase agreements as well as the remaining contractual maturity of the repurchase agreements:

	Remaining contractual maturity of the agreements
	Overnight and continuous		Up to 30 days		30 - 90 days		Greater than 90 days		Total
June 30, 2015	(in thousands)
Class of collateral pledged for repurchase agreements
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	67,230	$	—	$	—	$	25,000	$	92,230
Gross amount of recognized liabilities for repurchase agreements									92,230
Amounts related to agreements not included in offsetting disclosure									$	—

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, 2015 and December 31, 2014:

	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, 2015
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	290,497	$	(2,468	)	$	200,514	$	(7,014	)	$	491,011	$	(9,482	)
State and municipal securities	123,367		(1,020		)	29,701		(980		)	153,068		(2,000		)
U.S. government agency and government-sponsored enterprise securities	128,033		(418		)	100,277		(1,466		)	228,310		(1,884		)
U.S. government securities	—		—			19,613		(262		)	19,613		(262		)
Other securities	2,304		(11		)	2,807		(148		)	5,111		(159		)
Total	$	544,201	$	(3,917	)	$	352,912	$	(9,870	)	$	897,113	$	(13,787	)
December 31, 2014
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	258,825	$	(1,287	)	$	279,015	$	(6,924	)	$	537,840	$	(8,211	)
State and municipal securities	71,026		(543		)	44,148		(982		)	115,174		(1,525		)
U.S. government agency and government-sponsored enterprise securities	105,250		(518		)	216,221		(3,551		)	321,471		(4,069		)
U.S. government securities	—		—			19,450		(411		)	19,450		(411		)
Other securities	2,313		(2		)	2,834		(121		)	5,147		(123		)
Total	$	437,414	$	(2,350	)	$	561,668	$	(11,989	)	$	999,082	$	(14,339	)