Securities Available-for-Sale

12 Months Ended

Dec. 31, 2011

Securities Available-for-Sale and Investment Securities Held-to-Maturity [Abstract]

Securities Available-for-Sale

3.     Securities Available-for-Sale

	December 31, 2011								December 31, 2010
			Gross		Gross		Estimated				Gross		Gross		Estimated
	Amortized		Unrealized		Unrealized		Fair		Amortized		Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value		Cost		Gains		Losses		Value
	(Dollars in thousands)
U.S. Treasury	$	1,999	$	13	$	—	$	2,012	$	2,000	$	5	$	—	$	2,005
U.S. Government Sponsored Enterprises		174,657		311		11		174,957		175,842		386		565		175,663
SBA Backed Securities		8,714		87		—		8,801		9,735		1		4		9,732
U.S. Government Agency and Sponsored Enterprises Mortgage-Backed Securities		1,020,752		16,262		1,176		1,035,838		674,481		11,842		5,425		680,898
Privately Issued Residential
Mortgage-Backed Securities		3,509		—		311		3,198		4,247		—		279		3,968
Privately Issued Commercial
Mortgage-Backed Securities		—		—		—		—		285		2		—		287
Obligations Issued by States and Political Subdivisions		21,515		84		957		20,642		34,271		98		295		34,074
Other Debt Securities		13,293		—		683		12,610		2,300		—		47		2,253
Equity Securities		533		85		—		618		395		116		—		511
Total	$	1,244,972	$	16,842	$	3,138	$	1,258,676	$	903,556	$	12,450	$	6,615	$	909,391

Included in U.S. Government Sponsored Enterprise Securities and U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities are securities at fair value pledged to secure public deposits and repurchase agreements amounting to $488,690,000 and $363,240,000 at December 31, 2011 and 2010, respectively. Also included in securities available-for-sale at fair value are securities pledged for borrowing at the Federal Home Loan Bank amounting to $246,036,000 and $124,189,000 at December 31, 2011 and 2010, respectively. The Company realized gains on sales of securities of $1,940,000, $1,851,000 and $2,734,000 from the proceeds of sales of available-for-sale securities of $75,615,000, $41,251,000 and $94,142,000 for the years ended December 31, 2011, 2010, and 2009, respectively.

Debt securities of Government Sponsored Enterprises primarily refer to debt securities of Fannie Mae and Freddie Mac. Control of these enterprises was directly taken over by the U.S. Government in the third quarter of 2008.

The following table shows the estimated maturity distribution of the Company’s securities available-for-sale at December 31, 2011.

	Amortized		Fair
	Cost		Value
	(Dollars in thousands)
Within one year	$	79,863	$	80,608
After one but within five years		952,351		965,828
After five but within ten years		191,667		191,495
More than ten years		19,058		18,659
Nonmaturing		2,033		2,086
Total	$	1,244,972	$	1,258,676

The weighted average remaining life of investment securities available-for-sale at December 31, 2011, was 3.9 years. An auction rate municipal obligation (“ARS”) is included in Obligations Issued by States and Political Subdivisions. Included in the weighted average remaining life calculation at December 31, 2011, was $154,657,000 of U.S. Government Sponsored Enterprise obligations that are callable at the discretion of the issuer. These call dates were not utilized in computing the weighted average remaining life. The contractual maturities, which were used in the table above, of mortgage-backed securities, will differ from the actual maturities due to the ability of the issuers to prepay underlying obligations.

The following table shows the temporarily impaired securities of the Company’s available-for-sale portfolio at December 31, 2011. This table shows the unrealized loss of securities that have been in a continuous unrealized loss position for 12 months or less and a continuous loss position for 12 months and longer. There are 60 and 6 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 393 holdings at December 31, 2011.

As of December 31, 2011, management concluded that the unrealized losses of its investment securities are temporary in nature since they are not related to the underlying credit quality of the issuers, and the Company does not intend to sell any of its debt securities and it is not likely that it will be required to sell the debt securities before the anticipated recovery of their remaining amortized cost. In making its other-than-temporary impairment evaluation, the Company considered the fact that the principal and interest on these securities are from issuers that are investment grade. The change in the unrealized losses on the state and municipal securities and the nonagency mortgage-backed securities was primarily caused by changes in credit spreads and liquidity issues in the marketplace.

In evaluating the underlying credit quality of a security, management considers several factors such as the credit rating of the obligor and the issuer, if applicable. Internal reviews of issuer financial statements are performed as deemed necessary. In the case of privately issued mortgage-backed securities, the performance of the underlying loans is analyzed as deemed necessary to determine the estimated future cash flows of the securities. Factors considered include the level of subordination, current and estimated future default rates, current and estimated prepayment rates, estimated loss severity rates, geographic concentrates and origination dates of underlying loans. In the case of marketable equity securities, the severity of the unrealized loss, the length of time the unrealized loss has existed, and the issuer’s financial performance are considered.

	December 31, 2011
	Less Than 12 Months				12 Months or Longer				Total
			Unrealized				Unrealized				Unrealized
Temporarily Impaired Investments	Fair Value		Losses		Fair Value		Losses		Fair Value		Losses
	(Dollars in thousands)
U.S. Government Sponsored Enterprise	$	14,989	$	11	$	—	$	—	$	14,989	$	11
U.S. Government Agency and Sponsored
Enterprise Mortgage-Backed Securities		331,469		1,176		—		—		331,469		1,176
Privately Issued Residential Mortgage-Backed Securities		—		—		3,198		311		3,198		311
Obligations Issued by States and Political Subdivisions		—		—		3,725		957		3,725		957
Other Debt Securities		10,542		652		1,468		31		12,010		683
Equity Securities		—		—		—		—		—		—
Total temporarily impaired securities	$	357,000	$	1,839	$	8,391	$	1,299	$	365,391	$	3,138

At December 31, 2011, the Company does not intend to sell any of its debt securities and it is not likely that it will be required to sell the debt securities before the anticipated recovery of their remaining amortized cost. The unrealized losses on Obligations Issued by States and Political Subdivisions were considered by management to be temporary in nature. Full collection of those debt securities is expected because the financial condition of the obligors is considered to be sound, there has been no default in scheduled payment and the debt securities are rated investment grade. The unrealized loss on U.S. Government Sponsored Enterprises and U.S. Government Sponsored Enterprises Mortgage-Backed Securities related primarily to interest rates and not credit quality, and because the Company has the ability and intent to hold these investments until recovery of fair value, which may be maturity, the Company does not consider these investments to be other-than-temporarily impaired at December 31, 2011. Excluded from the table above are two equity securities that were written down in 2008 by $76,000. The fair value is $141,000 with an unrealized gain of $32,000 at December 31, 2011. In 2008, these stocks were deemed to be other-than-temporarily impaired based on the extent of the decline in value and the length of time the stocks had been trading below cost.

The following table shows the temporarily impaired securities of the Company’s available-for-sale portfolio at December 31, 2010. This table shows the unrealized loss of securities that have been in a continuous unrealized loss position for 12 months or less and a continuous loss position for 12 months and longer. There are 59 and 5 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 345 holdings at December 31, 2010.

	December 31, 2010
	Less Than 12 Months				12 Months or Longer				Total
			Unrealized				Unrealized				Unrealized
Temporarily Impaired Investments	Fair Value		Losses		Fair Value		Losses		Fair Value		Losses
	(Dollars in thousands)
U.S. Government Sponsored Enterprises	$	74,290	$	565	$	—	$	—	$	74,290	$	565
SBA Backed Securities		2,246		4		—		—		2,246		4
U.S. Government Agency and Sponsored
Enterprises Mortgage-Backed Securities		191,155		5,425		—		—		191,155		5,425
Privately Issued Residential Mortgage-Backed Securities		1,503		52		2,465		227		3,968		279
Obligations Issued by States and Political Subdivisions		9,257		11		4,393		284		13,650		295
Other Debt Securities		—		—		1,454		47		1,454		47
Equity Securities		—		—		—		—		—		—
Total temporarily impaired securities	$	278,451	$	6,057	$	8,312	$	558	$	286,763	$	6,615

At December 31, 2010, the Company does not intend to sell any of its debt securities and it is not likely that it will be required to sell the debt securities before the anticipated recovery of their remaining amortized cost. The unrealized losses on Obligations Issued by States and Political Subdivisions were considered by management to be temporary in nature. Full collection of those debt securities is expected because the financial condition of the obligors is considered to be sound, there has been no default in scheduled payment and the debt securities are rated investment grade. The unrealized loss on U.S. Government Sponsored Enterprises and U.S. Government Sponsored Enterprises Mortgage-Backed Securities related primarily to interest rates and not credit quality, and because the Company has the ability and intent to hold these investments until recovery of fair value, which may be maturity, the Company does not consider these investments to be other-than-temporarily impaired at December 31, 2010. Excluded from the table above are two equity securities that were written down in 2008 by $76,000. The fair value is $156,000 with an unrealized gain of $47,000 at December 31, 2010. In 2008, these stocks were deemed to be other-than-temporarily impaired based on the extent of the decline in value and the length of time the stocks had been trading below cost.