Investment Securities (Tables)

9 Months Ended

Sep. 30, 2013

Investments Debt And Equity Securities [Abstract]

Amortized Cost and Estimated Fair Value of Held-to-Maturity Securities and Available-for-Sale Securities by Contractual Maturity

The following table shows the amortized cost and the estimated fair value of the held-to-maturity securities and available-for-sale securities at September 30, 2013 and December 31, 2012 by contractual maturity within each type:

	At September 30, 2013									At December 31, 2012
(Dollars in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Securities Held-to-Maturity
Corporate bonds:
Within 1 year	$	12,228	$	86	$	—		$	12,314	$	3,026	$	7	$	—		$	3,033
After 1 year to 5 years		56,986		1,040		(261	)		57,765		66,819		1,526		(51	)		68,294
		69,214		1,126		(261	)		70,079		69,845		1,533		(51	)		71,327
Total	$	69,214	$	1,126	$	(261	)	$	70,079	$	69,845	$	1,533	$	(51	)	$	71,327
Securities Available-for-Sale
U.S. treasuries:
After 5 years to 10 years	$	4,965	$	—	$	(192	)	$	4,773	$	4,960	$	—	$	(22	)	$	4,938
		4,965		—		(192	)		4,773		4,960		—		(22	)		4,938
U.S. government corporations and agencies:
Within 1 year		5,999		36		—			6,035		1,517		9		—			1,526
After 1 year to 5 years		148,123		169		(1,157	)		147,135		148,120		1,509		(70	)		149,559
After 5 years to 10 years		10,850		—		(471	)		10,379		20,953		109		(5	)		21,057
		164,972		205		(1,628	)		163,549		170,590		1,627		(75	)		172,142
State and political subdivisions:
Within 1 year		3,825		14		—			3,839		4,607		75		—			4,682
After 1 year to 5 years		4,603		29		(35	)		4,597		4,130		88		(19	)		4,199
After 5 years to 10 years		41,545		720		(530	)		41,735		36,499		1,245		(7	)		37,737
Over 10 years		65,746		1,788		(311	)		67,223		70,495		5,055		—			75,550
		115,719		2,551		(876	)		117,394		115,731		6,463		(26	)		122,168
Residential mortgage-backed securities:
After 5 years to 10 years		18,365		307		(55	)		18,617		20,140		777		—			20,917
Over 10 years		35,075		375		—			35,450		66,962		2,861		—			69,823
		53,440		682		(55	)		54,067		87,102		3,638		—			90,740
Collateralized mortgage obligations:
After 1 year to 5 years		109		1		—			110		41		—		—			41
After 5 years to 10 years		—		—		—			—		626		7		—			633
Over 10 years		9,462		111		(163	)		9,410		25,698		645		(5	)		26,338
		9,571		112		(163	)		9,520		26,365		652		(5	)		27,012
Corporate bonds:
After 1 year to 5 years		10,819		35		(131	)		10,723		4,993		21		—			5,014
After 5 years to 10 years		22,833		8		(1,156	)		21,685		—		—		—			—
		33,652		43		(1,287	)		32,408		4,993		21		—			5,014
Money market mutual funds:
Within 1 year		9,639		—		—			9,639		4,878		—		—			4,878
		9,639		—		—			9,639		4,878		—		—			4,878
Equity securities:
No stated maturity		1,678		357		(26	)		2,009		2,279		696		(133	)		2,842
		1,678		357		(26	)		2,009		2,279		696		(133	)		2,842
Total	$	393,636	$	3,950	$	(4,227	)	$	393,359	$	416,898	$	13,097	$	(261	)	$	429,734

Information Related to Sales of Securities Available-for-Sale

The following table presents information related to sales of securities available-for-sale during the nine months ended September 30, 2013 and 2012:

	Nine Months Ended September 30,
(Dollars in thousands)	2013		2012
Securities available-for-sale:
Proceeds from sales	$	58,148	$	57,162
Gross realized gains on sales		2,957		1,187
Gross realized losses on sales		7		896
Tax expense related to net realized gains on sales		1,033		102

Amount of Securities in Unrealized Loss Position

The following table shows the fair value of securities that were in an unrealized loss position at September 30, 2013 and December 31, 2012 by the length of time those securities were in a continuous loss position:

	At September 30, 2013
	Less than Twelve Months					Twelve Months or Longer				Total
(Dollars in thousands)	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
U.S. treasuries	$	4,773	$	(192	)	$	—	$	—	$	4,773	$	(192	)
U.S. government corporations and agencies		107,154		(1,628	)		—		—		107,154		(1,628	)
State and political subdivisions		26,790		(876	)		—		—		26,790		(876	)
Residential mortgage-backed securities		5,093		(55	)		—		—		5,093		(55	)
Collateralized mortgage obligations		4,334		(163	)		—		—		4,334		(163	)
Corporate bonds		45,866		(1,548	)		—		—		45,866		(1,548	)
Equity securities		1,054		(26	)		—		—		1,054		(26	)
Total	$	195,064	$	(4,488	)	$	—	$	—	$	195,064	$	(4,488	)

	At December 31, 2012
	Less than Twelve Months					Twelve Months or Longer					Total
(Dollars in thousands)	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
U.S. treasuries	$	4,938	$	(22	)	$	—	$	—		$	4,938	$	(22	)
U.S. government corporations and agencies		36,793		(75	)		—		—			36,793		(75	)
State and political subdivisions		4,574		(14	)		480		(12	)		5,054		(26	)
Collateralized mortgage obligations		5,006		(5	)		—		—			5,006		(5	)
Corporate bonds		10,410		(51	)		—		—			10,410		(51	)
Equity securities		976		(133	)		—		—			976		(133	)
Total	$	62,697	$	(300	)	$	480	$	(12	)	$	63,177	$	(312	)