SECURITIES

The significant accounting policies related to securities are presented in Note 1, "Summary of Significant Accounting Policies" to the Consolidated Financial Statements in the Company's 2016 10-K.

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, 2017									As of December 31, 2016
	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. treasury securities	$	48,568	$	19	$	(104	)	$	48,483	$	48,581	$	26	$	(66	)	$	48,541
U.S. agency securities	174,757		599		(298		)	175,058		183,528		519		(410		)	183,637
Collateralized mortgage obligations ("CMOs")	1,017,896		1,086		(12,818		)	1,006,164		1,064,130		969		(17,653		)	1,047,446
Other mortgage-backed securities ("MBSs")	377,043		1,261		(4,644		)	373,660		337,139		1,395		(5,879		)	332,655
Municipal securities	262,906		2,446		(950		)	264,402		273,319		1,245		(3,718		)	270,846
Trust-preferred collateralized debt obligations ("CDOs")	47,740		279		(14,565		)	33,454		47,681		261		(14,682		)	33,260
Equity securities	7,106		154		(233		)	7,027		3,206		147		(288		)	3,065
Total securities available-for-sale	$	1,936,016	$	5,844	$	(33,612	)	$	1,908,248	$	1,957,584	$	4,562	$	(42,696	)	$	1,919,450
Securities Held-to-Maturity
Municipal securities	$	17,353	$	—	$	(2,454	)	$	14,899	$	22,291	$	—	$	(4,079	)	$	18,212
Trading Securities								$	19,545								$	17,920

Remaining Contractual Maturity of Securities

(Dollar amounts in thousands)



	As of June 30, 2017
	Available-for-Sale				Held-to-Maturity
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
One year or less	$	94,163	$	91,946	$	1,935	$	1,661
After one year to five years	362,886		354,341		6,321		5,427
After five years to ten years	2,595		2,533		2,259		1,940
After ten years	74,327		72,577		6,838		5,871
Securities that do not have a single contractual maturity date	1,402,045		1,386,851		—		—
Total	$	1,936,016	$	1,908,248	$	17,353	$	14,899

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 $1.1 billion for both June 30, 2017 and December 31, 2016. No securities held-to-maturity were pledged as of June 30, 2017 or December 31, 2016.

During the quarters and six months ended June 30, 2017 and 2016 there were no material gross trading gains (losses). The following table presents net realized gains on securities available-for-sale for the quarters and six months ended June 30, 2017 and 2016.

Securities Available-for-Sale Gains

(Dollar amounts in thousands)



	Quarters Ended June 30,					Six Months Ended June 30,
	2017		2016			2017		2016
Gains on sales of securities:
Gross realized gains	$	284	$	149		$	284	$	1,079
Gross realized losses	—		(126		)	—		(169		)
Net realized gains on sales of securities	284		23			284		910
Non-cash impairment charges:
Other-than-temporary securities impairment ("OTTI")	—		—			—		—
Net realized gains	$	284	$	23		$	284	$	910

Securities acquired in the Standard transaction in the first quarter of 2017 were sold shortly after the acquisition date for $210.2 million, resulting in no gains or losses as the securities were recorded at fair value upon acquisition.

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 outstanding balance of OTTI previously recognized on securities available-for-sale was $23.3 million for both June 30, 2017 and December 31, 2016. During the quarters and six months ended June 30, 2017 and 2016 there were no additions or reductions to the balance of OTTI related to securities available-for-sale.

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, 2017 and December 31, 2016.

Securities in an Unrealized Loss Position

(Dollar amounts in thousands)



		Less Than 12 Months				12 Months or Longer				Total
	Number of Securities	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
As of June 30, 2017
Securities Available-for-Sale
U.S. treasury securities	18	$	42,442	$	104	$	—	$	—	$	42,442	$	104
U.S. agency securities	36	68,096		245		13,235		53		81,331		298
CMOs	186	737,140		10,196		87,787		2,622		824,927		12,818
MBSs	73	287,409		4,235		21,101		409		308,510		4,644
Municipal securities	141	58,746		868		3,623		82		62,369		950
CDOs	7	—		—		30,744		14,565		30,744		14,565
Equity securities	2	—		—		6,778		233		6,778		233
Total	463	$	1,193,833	$	15,648	$	163,268	$	17,964	$	1,357,101	$	33,612
Securities Held-to-Maturity
Municipal securities	11	$	—	$	—	$	14,899	$	2,454	$	14,899	$	2,454
As of December 31, 2016
Securities Available-for-Sale
U.S. treasury securities	16	$	33,505	$	61	$	3,995	$	5	$	37,500	$	66
U.S. agency securities	28	62,064		364		11,814		46		73,878		410
CMOs	194	523,233		10,309		411,758		7,344		934,991		17,653
MBSs	68	221,174		4,726		77,780		1,154		298,954		5,880
Municipal securities	380	133,957		3,059		29,280		659		163,237		3,718
CDOs	7	—		—		30,592		14,682		30,592		14,682
Equity securities	2	404		201		2,319		86		2,723		287
Total	695	$	974,337	$	18,720	$	567,538	$	23,976	$	1,541,875	$	42,696
Securities Held-to-Maturity
Municipal securities	14	$	—	$	—	$	18,212	$	4,079	$	18,212	$	4,079

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, 2017 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, 2017 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 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. For a detailed discussion of the CDO valuation methodology, see Note 15, "Fair Value."