Securities (Tables)

6 Months Ended

Jun. 30, 2012

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, 2012
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	601,460	$	20,484	$	(666	)	$	621,278
State and municipal securities	258,774		20,231		(198		)	278,807
U.S. government agency and government-sponsored enterprise securities	93,092		1,211		(9		)	94,294
Other securities	3,310		105		(31		)	3,384
Total	$	956,636	$	42,031	$	(904	)	$	997,763
December 31, 2011
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	678,631	$	19,323	$	(2,000	)	$	695,954
State and municipal securities	263,075		22,746		(58		)	285,763
U.S. government agency and government-sponsored enterprise securities	42,558		505		—			43,063
Other securities	3,296		64		(30		)	3,330
Total	$	987,560	$	42,638	$	(2,088	)	$	1,028,110

Schedule of Contractual Maturities of Investment Securities Available for Sale

The scheduled contractual maturities of investment securities available for sale at June 30, 2012 are presented as follows:

	June 30, 2012
	Amortized Cost		Fair Value
	(in thousands)
Due within one year	$	18,270	$	18,553
Due after one year through five years	139,044		142,225
Due after five years through ten years	169,482		178,051
Due after ten years	626,530		655,550
Other securities with no stated maturity	3,310		3,384
Total investment securities available-for-sale	$	956,636	$	997,763

Carrying Value of Securities Pledged As Collateral

The following table summarizes, as of June 30, 2012, 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)
To Washington and Oregon State to secure public deposits	$	266,499
To Federal Home Loan Bank to secure advances	80,890
To Federal Reserve Bank to secure borrowings	51,454
Other securities pledged	49,014
Total securities pledged as collateral	$	447,857

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

The following tables show 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, 2012 and December 31, 2011:

	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, 2012
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	85,516	$	(664	)	$	66	$	(2	)	$	85,582	(666		)
State and municipal securities	9,173		(198		)	—		—			9,173		(198		)
U.S. government agency and government-sponsored enterprise securities	24,870		(9		)	—		—			24,870		(9		)
Other securities	—		—			969		(31		)	969		(31		)
Total	$	119,559	$	(871	)	$	1,035	$	(33	)	$	120,594	$	(904	)
December 31, 2011
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	238,875	$	(1,999	)	$	196	$	(1	)	$	239,071	$	(2,000	)
State and municipal securities	3,820		(24		)	950		(34		)	4,770		(58		)
Other securities	—		—			970		(30		)	970		(30		)
Total	$	242,695	$	(2,023	)	$	2,116	$	(65	)	$	244,811	$	(2,088	)