(4) SECURITIES

The following table summarizes securities held for investment and securities available for sale:


	December 31,
	2011		2010
	(Dollars in thousands)
Held for investment at cost (market value: $22,958 and $22,640, respectively)	$	22,477	$	22,011
Available for sale, at market value		592,500		721,792

Total	$	614,977	$	743,803

The following table summarizes the amortized cost and estimated market values of securities held for investment:


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Market Value
	(Dollars in thousands)
December 31, 2011
U.S. Treasury and other Federal agencies	$	997	$	75	$	—		$	1,072
States and political subdivisions		21,480		406		—			21,886

Total	$	22,477	$	481	$	—		$	22,958

December 31, 2010
U.S. Treasury and other Federal agencies	$	1,207	$	82	$	—		$	1,289
States and political subdivisions		20,804		556		(9	)		21,351

Total	$	22,011	$	638	$	(9	)	$	22,640

The following table summarizes the amortized cost and estimated market values of securities available for sale:


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Market Value
	(Dollars in thousands)
December 31, 2011
U.S. Treasuries	$	—	$	—	$	—		$	—
U.S. Federal agencies (1)		481,486		6,673		(116	)		488,043
Mortgage backed securities		28,984		615		(13	)		29,586
States and political subdivisions		60,239		2,490		(20	)		62,709
Other securities (2)		7,222		4,940		—			12,162

Total	$	577,931	$	14,718	$	(149	)	$	592,500

December 31, 2010
U.S. Treasuries	$	64,962	$	8	$	—		$	64,970
U.S. Federal agencies (1)		560,247		11,177		(719	)		570,705
Mortgage backed securities		10,779		222		(11	)		10,990
States and political subdivisions		65,115		235		(1,140	)		64,210
Other securities (2)		7,686		3,653		(422	)		10,917

Total	$	708,789	$	15,295	$	(2,292	)	$	721,792

(1)	Primarily consists of FHLMC, FNMA, GNMA and mortgage backed securities through U.S. agencies.

(2)	Primarily consists of government guaranteed corporate bonds and equity securities.

The maturities of securities held for investment and available for sale are summarized in the following table using contractual maturities. Actual maturities may differ from contractual maturities due to obligations that are called or prepaid. For purposes of the maturity table, mortgage-backed securities, which are not due at a single maturity date, have been presented at their contractual maturity.


	December 31,
	2011				2010
	Amortized Cost		Estimated Market Value		Amortized Cost		Estimated Market Value
	(Dollars in thousands)
Held for Investment
Contractual maturity of debt securities:
Within one year	$	5,845	$	5,908	$	5,722	$	5,779
After one year but within five years		13,967		14,256		12,815		13,267
After five years but within ten years		1,883		1,943		2,483		2,528
After ten years		782		851		991		1,066

Total	$	22,477	$	22,958	$	22,011	$	22,640

Available for Sale
Contractual maturity of debt securities:
Within one year	$	105,169	$	107,109	$	360,682	$	362,149
After one year but within five years		317,979		321,661		168,310		177,781
After five years but within ten years		61,412		63,358		69,276		68,390
After ten years		86,149		88,210		102,914		102,635

Total debt securities		570,709		580,338		701,182		710,955
Equity securities		7,222		12,162		7,607		10,837

Total	$	577,931	$	592,500	$	708,789	$	721,792

The following is a detail of proceeds from sales and calls, and realized securities gains and losses, on available for sale securities:


	Year Ended December 31,
	2011		2010		2009
	(Dollars in thousands)
Proceeds	$	94,658	$	5,783	$	7,413
Gross gains realized		1,940		528		380
Gross losses realized		342		204		44

The following table is a summary of the Company's book value of securities that were pledged as collateral for public funds on deposit, repurchase agreements and for other purposes as required or permitted by law:


	Year Ended December 31,
	2011		2010
	(Dollars in thousands)
Book value of pledged securities	$	527,211	$	628,911

The following table summarizes securities with unrealized losses, segregated by the duration of the unrealized loss, at December 31, 2011 and 2010 respectively:


	Less than 12 Months				More than 12 Months				Total
	Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses
	(Dollars in thousands)
December 31, 2011
Held for Investment
U.S. Federal agencies	$	—	$	—	$	—	$	—	$	—	$	—
States and political subdivisions		205		—		—		—		205		—

Total	$	205	$	—	$	—	$	—	$	205	$	—

Available for Sale
U.S. Federal agencies	$	—	$	—	$	148,576	$	116	$	148,576	$	116
States and political subdivisions		40		—		3,571		33		3,611		33

Total	$	40	$	—	$	152,147	$	149	$	152,187	$	149

December 31, 2010
Held for Investment
U.S. Federal agencies	$	—	$	—	$	—	$	—	$	—	$	—
States and political subdivisions		105		—		521		9		626		9

Total	$	105	$	—	$	521	$	9	$	626	$	9

Available for Sale
U.S. Federal agencies	$	20,442	$	23	$	59,703	$	1,129	$	80,145	$	1,152
States and political subdivisions		357		2		51,973		1,138		52,330		1,140

Total	$	20,799	$	25	$	111,676	$	2,267	$	132,475	$	2,292

Declines in the fair value of held for investment and available-for-sale securities below their cost that are deemed to be other than temporary are reflected in earnings as realized losses. In estimating other-than-temporary impairment losses, management considers, among other things, (i) the length of time and the extent to which the fair value has been less than cost, (ii) the financial condition and near-term prospects of the issuer, and (iii) the intent and ability of the Company to retain its investment in the issuer for a period of time sufficient to allow for any anticipated recovery in fair value.

Management has the ability and intent to hold the securities classified as held for investment until they mature, at which time the Company will receive full value for the securities. Furthermore, as of December 31, 2011 and 2010, the Company also had the ability and intent to hold the securities classified as available for sale for a period of time sufficient for a recovery of cost. The unrealized losses are largely due to increases in market interest rates over the yields available at the time the underlying debt securities were purchased. The fair value is expected to recover as the securities approach their maturity date or repricing date or if market yields for such investments decline. Management does not believe any of the securities are impaired due to reasons of credit quality and therefore has not recognized any impairment in the Company's consolidated statement of comprehensive income.