SECURITIES

Securities are classified as held-to-maturity, trading, or available-for-sale at the time of purchase. Securities classified as held-to-maturity are securities for which management has the intent and ability to hold to maturity and are stated at cost.

The Company's trading securities consist of diversified investment securities reported at fair value that are held in a grantor trust under deferred compensation arrangements in which plan participants may direct amounts earned to be invested in securities other than Company stock.

All other securities are classified as available-for-sale and are carried at fair value with unrealized gains and losses, net of related deferred income taxes, recorded in stockholders' equity as a separate component of accumulated other comprehensive loss.

A summary of the Company's securities portfolio by category and maturity is presented in the following tables.

Securities Portfolio

(Dollar amounts in thousands)



	As of June 30, 2015									As of December 31, 2014
	Amortized Cost		Gross Unrealized					Fair Value		Amortized Cost		Gross Unrealized					Fair Value
	Amortized Cost		Gains		Losses			Fair Value		Amortized Cost		Gains		Losses			Fair Value
Securities Available-for-Sale
U.S. agency securities	$	20,312	$	172	$	—		$	20,484	$	30,297	$	144	$	(10	)	$	30,431
Collateralized mortgage obligations ("CMOs")	525,357		2,328		(6,110		)	521,575		538,882		2,256		(6,982		)	534,156
Other mortgage-backed securities ("MBSs")	179,436		3,198		(791		)	181,843		155,443		4,632		(310		)	159,765
Municipal securities	377,381		7,319		(1,712		)	382,988		414,255		10,583		(1,018		)	423,820
Trust preferred collateralized debt obligations ("CDOs")	48,231		77		(16,304		)	32,004		48,502		152		(14,880		)	33,774
Corporate debt securities	31		49		—			80		1,719		83		—			1,802
Equity securities	3,377		100		(44		)	3,433		3,224		72		(35		)	3,261
Total available- for-sale securities	$	1,154,125	$	13,243	$	(24,961	)	$	1,142,407	$	1,192,322	$	17,922	$	(23,235	)	$	1,187,009
Securities Held-to-Maturity
Municipal securities	$	24,292	$	253	$	—		$	24,545	$	26,555	$	1,115	$	—		$	27,670
Trading Securities								$	18,172								$	17,460

Remaining Contractual Maturity of Securities

(Dollar amounts in thousands)



	As of June 30, 2015
	Available-for-Sale				Held-to-Maturity
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
One year or less	$	114,934	$	112,254	$	2,330	$	2,354
After one year to five years	104,940		102,493		8,497		8,585
After five years to ten years	177,819		173,672		4,947		4,999
After ten years	48,262		47,137		8,518		8,607
Securities that do not have a single contractual maturity date	708,170		706,851		—		—
Total	$	1,154,125	$	1,142,407	$	24,292	$	24,545

The carrying value of securities available-for-sale that were pledged to secure deposits or for other purposes as permitted or required by law totaled $959.8 million at June 30, 2015 and $779.4 million at December 31, 2014. No securities held-to-maturity were pledged as of June 30, 2015 or December 31, 2014.

Purchases and sales of securities are recognized on a trade date basis. Realized securities gains or losses are reported in net securities gains in the Condensed Consolidated Statements of Income. The cost of securities sold is based on the specific identification method. During the quarters and six months ended June 30, 2015 and 2014 there were no material gross trading gains (losses). The following table presents net realized gains on available-for-sale securities for the quarters and six months ended June 30, 2015 and 2014.

Available-for-Sale Securities Gains (Losses)

(Dollar amounts in thousands)



	Quarters Ended June 30,				Six Months Ended June 30,
	2015		2014		2015			2014
Gains (losses) on sales of securities:
Gross realized gains	$	515	$	4,517	$	1,165		$	5,618
Gross realized losses	—		—		(138		)	—
Net realized gains on sales of securities	515		4,517		1,027			5,618
Non-cash impairment charges:
Other-than-temporary securities impairment ("OTTI")	—		—		—			(28		)
Net realized gains	$	515	$	4,517	$	1,027		$	5,590

Accounting guidance requires that the credit portion of an OTTI charge be recognized through income. If a decline in fair value below carrying value is not attributable to credit deterioration and the Company does not intend to sell the security or believe it would not be more likely than not required to sell the security prior to recovery, the Company records the non-credit related portion of the decline in fair value in other comprehensive income.

The following table presents a rollforward of life-to-date OTTI recognized in earnings related to all available-for-sale securities held by the Company for the quarters and six months ended June 30, 2015 and 2014. The majority of the beginning and ending balance of OTTI relates to CDOs currently held by the Company.

Changes in OTTI Recognized in Earnings

(Dollar amounts in thousands)



	Quarters Ended June 30,					Six Months Ended June 30,
	2015		2014			2015			2014
Beginning balance	$	23,709	$	32,450		$	23,880		$	32,422
OTTI included in earnings ⁽¹⁾:
Losses on securities that previously had OTTI	—		—			—			28
Reduction for sales of securities ⁽²⁾	—		(8,570		)	(171		)	(8,570		)
Ending balance	$	23,709	$	23,880		$	23,709		$	23,880


⁽¹⁾	Included in net securities gains in the Condensed Consolidated Statements of Income.


⁽²⁾	During the six months ended June 30, 2015, the Company sold one CMO with a carrying value of $1.3 million that had OTTI of $171,000 that was previously recognized in earnings. The Company sold one CDO with a carrying value of $1.3 million during the second quarter of 2014 that had OTTI of $8.6 million that was previously recognized in earnings.

The following table presents the aggregate amount of unrealized losses and the aggregate related fair values of securities with unrealized losses as of June 30, 2015 and December 31, 2014.

Securities in an Unrealized Loss Position

(Dollar amounts in thousands)



		Less Than 12 Months				Greater Than 12 Months				Total
	Number of Securities	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
As of June 30, 2015
CMOs	74	$	82,431	$	778	$	233,676	$	5,332	$	316,107	$	6,110
MBSs	20	56,341		316		34,405		475		90,746		791
Municipal securities	155	21,714		328		56,520		1,384		78,234		1,712
CDOs	7	1,077		170		28,413		16,134		29,490		16,304
Equity securities	1	—		—		2,286		44		2,286		44
Total	257	$	161,563	$	1,592	$	355,300	$	23,369	$	516,863	$	24,961
As of December 31, 2014
U.S. agency securities	1	$	1,943	$	10	$	—	$	—	$	1,943	$	10
CMOs	87	61,321		559		284,327		6,423		345,648		6,982
MBSs	11	1,113		1		39,043		309		40,156		310
Municipal securities	91	1,317		9		53,987		1,009		55,304		1,018
CDOs	4	—		—		22,791		14,880		22,791		14,880
Equity securities	1	—		—		2,270		35		2,270		35
Total	195	$	65,694	$	579	$	402,418	$	22,656	$	468,112	$	23,235

Substantially all of the Company's CMOs and other MBSs are either backed by U.S. government-owned agencies or issued by U.S. government-sponsored enterprises. Municipal securities are issued by municipal authorities, and the majority are supported by third party insurance or some other form of credit enhancement. Management does not believe any of these securities with unrealized losses as of June 30, 2015 represent OTTI related to credit deterioration. These unrealized losses are attributed to changes in interest rates and temporary market movements. The Company does not intend to sell these securities and it is not more likely than not that the Company will be required to sell them before recovery of their amortized cost basis, which may be at maturity.

The unrealized losses on CDOs as of June 30, 2015 reflect changes in market activity for these securities. Management does not believe these unrealized losses represent OTTI related to credit deterioration. In addition, the Company does not intend to sell the CDOs with unrealized losses within a short period of time, and the Company does not believe it is more likely than not that it will be required to sell them before recovery of their amortized cost basis, which may be at maturity. Significant judgment is required to calculate the fair value of the CDOs, all of which are pooled. For a detailed discussion of the CDO valuation methodology, see Note 12, "Fair Value."