Securities (Tables)

3 Months Ended

Mar. 31, 2013

Securities

Schedule of amortized cost, unrealized gains and losses and fair values of securities classified available for sale

			Gross		Gross
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
	(dollars in thousands)
March 31, 2013:
U.S. Treasury securities	$	103,225	$	1,292	$	—		$	104,517
Obligations of U.S. government corporations and agencies	332,583		5,644		(16		)	338,211
Obligations of states and political subdivisions	276,195		5,819		(220		)	281,794
Residential mortgage-backed securities	190,989		7,105		—			198,094
Corporate debt securities	24,484		154		(10		)	24,628
Total debt securities	927,476		20,014		(246		)	947,244
Mutual funds and other equity securities	3,563		1,772		—			5,335
	$	931,039	$	21,786	$	(246	)	$	952,579

			Gross		Gross
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
	(dollars in thousands)
December 31, 2012:
U.S. Treasury securities	$	103,353	$	1,303	$	—		$	104,656
Obligations of U.S. government corporations and agencies	363,583		6,616		(5		)	370,194
Obligations of states and political subdivisions	274,350		6,176		(238		)	280,288
Residential mortgage-backed securities	210,139		7,576		—			217,715
Corporate debt securities	24,601		139		(26		)	24,714
Total debt securities	976,026		21,810		(269		)	997,567
Mutual funds and other equity securities	2,451		1,479		—			3,930
	$	978,477	$	23,289	$	(269	)	$	1,001,497

Schedule of amortized cost and fair value of debt securities available for sale by contractual maturity

	Amortized		Fair
	Cost		Value
	(dollars in thousands)
Due in one year or less	$	143,583	$	144,951
Due after one year through five years	518,792		527,045
Due after five years through ten years	202,954		209,884
Due after ten years	62,147		65,364
	$	927,476	$	947,244

Schedule of securities with gross unrealized losses aggregated by investment category and length of time that individual securities have been in continuous loss position

	Less than 12 months				Greater than 12 months				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
	(dollars in thousands)
March 31, 2013:
U.S. Treasury securities(1)	$	355	$	—	$	—	$	—	$	355	$	—
Obligations of U.S. government corporations and agencies	10,144		16		—		—		10,144		16
Obligations of states and political subdivisions	26,454		164		4,282		56		30,736		220
Corporate debt securities	7,159		10		—		—		7,159		10
Total temporarily impaired securities	$	44,112	$	190	$	4,282	$	56	$	48,394	$	246

(1)Unrealized loss was less than one thousand dollars.

	Less than 12 months				Greater than 12 months				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
	(dollars in thousands)
December 31, 2012:
Obligations of U.S. government corporations and agencies	$	10,155	$	5	$	—	$	—	$	10,155	$	5
Obligations of states and political subdivisions	37,958		189		3,311		49		41,269		238
Corporate debt securities	15,207		26		—		—		15,207		26
Total temporarily impaired securities	$	63,320	$	220	$	3,311	$	49	$	66,631	$	269