Investment Securities (Tables)

9 Months Ended

Sep. 30, 2014

Investments, Debt and Equity Securities [Abstract]

Amortized Cost and Estimated Fair Values of Investments in Debt and Equity Securities

The amortized cost and estimated fair values of investments in debt and equity securities are summarized in the following tables:

	September 30, 2014
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
	(in thousands)
Securities Available for Sale
Obligations of U.S. government corporations and agencies	$	75,877	$	4,095	$	(112	)	$	79,860
Obligations of states and political subdivisions		3,129		61		—			3,190
Corporate debt securities		1,887		25		—			1,912
Total securities available for sale	$	80,893	$	4,181	$	(112	)	$	84,962
Securities Held to Maturity
Obligations of U.S. government corporations and agencies	$	430,899	$	5,337	$	(1,930	)	$	434,306
Obligations of states and political subdivisions		12,610		22		(134	)		12,498
Total securities held to maturity	$	443,509	$	5,359	$	(2,064	)	$	446,804

	December 31, 2013
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
	(in thousands)
Securities Available for Sale
Obligations of U.S. government corporations and agencies	$	93,055	$	4,445	$	(357	)	$	97,143
Obligations of states and political subdivisions		5,513		77		(1	)		5,589
Corporate debt securities		1,877		38		—			1,915
Total securities available for sale	$	100,445	$	4,560	$	(358	)	$	104,647
Securities Held to Maturity
Obligations of U.S. government corporations and agencies	$	227,864	$	298	$	(5,540	)	$	222,622
Obligations of states and political subdivisions		12,640		—		(1,455	)		11,185
Total securities held to maturity	$	240,504	$	298	$	(6,995	)	$	233,807

Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity

For purposes of the following table, the entire outstanding balance of these mortgage-backed securities issued by U.S. government corporations and agencies is categorized based on final maturity date. 

Investment Securities	Available for Sale				Held to Maturity
(In thousands)	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due in one year	$	2,012	$	2,044		—		—
Due after one year through five years		1,193		1,244		—		—
Due after five years through ten years		33,218		34,556		—		—
Due after ten years		44,470		47,118	$	443,509	$	446,804
Totals	$	80,893	$	84,962	$	443,509	$	446,804

Gross Unrealized Losses on Investment

Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, were as follows:

	Less than 12 months					12 months or more					Total
	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss			Fair Value		Unrealized Loss
	(in thousands)
September 30, 2014
Securities available for sale:
Obligations of U.S. government corporations and agencies	$	2,631	$	(16	)	$	6,956	$	(96	)	$	9,587	$	(112	)
Obligations of states and political subdivisions		—		—			—		—			—		—
Corporate debt securities		—		—			—		—			—		—
Total securities available for sale	$	2,631	$	(16	)	$	6,956	$	(96	)	$	9,587	$	(112	)
Securities held to maturity:
Obligations of U.S. government corporations and agencies	$	46,073	$	(134	)	$	56,245	$	(1,796	)	$	102,318	$	(1,930	)
Obligations of states and political subdivisions		788		(22	)		7,357		(112	)		8,145		(134	)
Total securities held to maturity	$	46,861	$	(156	)	$	63,602	$	(1,908	)	$	110,463	$	(2,064	)
	Less than 12 months					12 months or more					Total
	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss			Fair Value		Unrealized Loss
	(in thousands)
December 31, 2013
Securities available for sale:
Obligations of U.S. government corporations and agencies	$	10,287	$	(357	)		—		—		$	10,287	$	(357	)
Obligations of states and political subdivisions		199		(1	)		—		—			199		(1	)
Corporate debt securities		—		—			—		—			—		—
Total securities available for sale	$	10,486	$	(358	)		—		—		$	10,486	$	(358	)
Securities held to maturity:
Obligations of U.S. government corporations and agencies	$	188,218	$	(5,540	)		—		—		$	188,218	$	(5,540	)
Obligations of states and political subdivisions		11,185		(1,455	)		—		—			11,185		(1,455	)
Total securities held to maturity	$	199,403	$	(6,995	)		—		—		$	199,403	$	(6,995	)