Securities (Tables)

6 Months Ended

Jun. 30, 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)
June 30, 2013:
U.S. Treasury securities	$	103,097	$	301	$	(223	)	$	103,175
Obligations of U.S. government corporations and agencies	311,442		3,723		(525		)	314,640
Obligations of states and political subdivisions	294,299		3,462		(2,694		)	295,067
Residential mortgage-backed securities	173,456		4,022		(237		)	177,241
Corporate debt securities	24,439		87		(90		)	24,436
Total debt securities	906,733		11,595		(3,769		)	914,559
Mutual funds and other equity securities	5,029		1,977		—			7,006
	$	911,762	$	13,572	$	(3,769	)	$	921,565

			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	$	160,492	$	161,813
Due after one year through five years	494,329		497,057
Due after five years through ten years	195,331		197,695
Due after ten years	56,581		57,994
	$	906,733	$	914,559

Schedule of realized gains and losses related to sales of securities

	Three Months Ended June 30,
	2013		2012
	(dollars in thousands)
Gross security gains	$	—	$	64
Gross security (losses)	—		—
Net security gains	$	—	$	64

	Six Months Ended June 30,
	2013		2012
	(dollars in thousands)
Gross security gains	$	—	$	64
Gross security (losses)	—		—
Net security gains	$	—	$	64

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)
June 30, 2013:
U.S. Treasury securities	$	51,050	$	223	$	—	$	—	$	51,050	$	223
Obligations of U.S. government corporations and agencies	25,119		525		—		—		25,119		525
Obligations of states and political subdivisions	129,570		2,617		4,489		77		134,059		2,694
Residential mortgage-backed securities	12,829		237		—		—		12,829		237
Corporate debt securities	20,186		90		—		—		20,186		90
Total temporarily impaired securities	$	238,754	$	3,692	$	4,489	$	77	$	243,243	$	3,769

	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