INVESTMENTS (Tables)

9 Months Ended

Sep. 30, 2017

Investments, Debt and Equity Securities [Abstract]

Summary of Held-To-Maturity and Available-For-Sale Investment Securities

The following is a summary of held-to-maturity and available-for-sale investment securities as of September 30, 2017:



	Held-to-maturity									Available-for-sale
(Dollars in thousands)	Amortized cost		Unrecognized gain		Unrecognized loss			Fair value		Amortized cost		Unrealized gain		Unrealized loss			Fair value
U.S. Treasuries	$	0	$	0	$	0		$	0	$	98	$	0	$	0		$	98
Securities of U.S. government agencies and corporations	11,588		33		(23		)	11,598		16,284		224		0			16,508
Mortgage-backed securities - residential	171,468		2,066		(1,219		)	172,315		272,254		1,471		(1,609		)	272,116
Mortgage-backed securities - commercial	257,590		2,655		(2,053		)	258,192		142,152		567		(521		)	142,198
Collateralized mortgage obligations	153,806		934		(915		)	153,825		304,679		1,551		(1,127		)	305,103
Obligations of state and other political subdivisions	75,364		1,184		(242		)	76,306		127,122		2,556		(701		)	128,977
Asset-backed securities	0		0		0			0		340,477		1,921		(517		)	341,881
Other securities	0		0		0			0		78,254		1,911		(276		)	79,889
Total	$	669,816	$	6,872	$	(4,452	)	$	672,236	$	1,281,320	$	10,201	$	(4,751	)	$	1,286,770

The following is a summary of held-to-maturity and available-for-sale investment securities as of December 31, 2016:



	Held-to-maturity									Available-for-sale
(Dollars in thousands)	Amortized cost		Unrecognized gain		Unrecognized loss			Fair value		Amortized cost		Unrealized gain		Unrealized loss			Fair value
U.S. Treasuries	$	0	$	0	$	0		$	0	$	98	$	0	$	(1	)	$	97
Securities of U.S. government agencies and corporations	13,011		0		(110		)	12,901		7,056		0		(40		)	7,016
Mortgage-backed securities - residential	205,522		1,740		(1,166		)	206,096		184,960		1,175		(2,740		)	183,395
Mortgage-backed securities - commercial	278,728		3,254		(1,817		)	280,165		154,239		188		(826		)	153,601
Collateralized mortgage obligations	195,408		1,125		(1,476		)	195,057		232,701		634		(2,321		)	231,014
Obligations of state and other political subdivisions	70,585		117		(1,346		)	69,356		96,934		1,461		(1,514		)	96,881
Asset-backed securities	0		0		0			0		322,708		517		(2,013		)	321,212
Other securities	0		0		0			0		46,641		741		(728		)	46,654
Total	$	763,254	$	6,236	$	(5,915	)	$	763,575	$	1,045,337	$	4,716	$	(10,183	)	$	1,039,870

Summary of Investment Securities by Estimated Maturity

The following table provides a summary of investment securities by contractual maturity as of September 30, 2017, except for residential and commercial mortgage-backed securities, collateralized mortgage obligations and asset-backed securities, which are shown as single totals, due to the unpredictability of the timing in principal repayments.



	Held-to-maturity				Available-for-sale
(Dollars in thousands)	Amortized cost		Fair value		Amortized cost		Fair value
By Contractual Maturity:
Due in one year or less	$	170	$	170	$	2,408	$	2,408
Due after one year through five years	4,466		4,469		26,795		27,154
Due after five years through ten years	2,690		2,849		78,265		79,868
Due after ten years	79,626		80,416		114,290		116,042
Mortgage-backed securities - residential	171,468		172,315		272,254		272,116
Mortgage-backed securities - commercial	257,590		258,192		142,152		142,198
Collateralized mortgage obligations	153,806		153,825		304,679		305,103
Asset-backed securities	0		0		340,477		341,881
Total	$	669,816	$	672,236	$	1,281,320	$	1,286,770

Age of Gross Unrealized Losses and Associated Fair Value by Investment Category

The following tables provide the fair value and gross unrealized losses on investment securities in an unrealized loss position, aggregated by investment category and the length of time the individual securities have been in a continuous loss position:



	September 30, 2017
	Less than 12 months					12 months or more					Total
(Dollars in thousands)	Fair value		Unrealized loss			Fair value		Unrealized loss			Fair value		Unrealized loss
Securities of U.S. Government agencies and corporations	$	6,275	$	(23	)	$	0	$	0		$	6,275	$	(23	)
Mortgage-backed securities - residential	71,312		(508		)	96,048		(2,320		)	167,360		(2,828		)
Mortgage-backed securities - commercial	67,611		(962		)	66,749		(1,612		)	134,360		(2,574		)
Collateralized mortgage obligations	124,023		(550		)	92,035		(1,492		)	216,058		(2,042		)
Obligations of state and other political subdivisions	58,858		(505		)	28,713		(438		)	87,571		(943		)
Asset-backed securities	23,707		(148		)	29,666		(369		)	53,373		(517		)
Other securities	7,278		(106		)	2,468		(170		)	9,746		(276		)
Total	$	359,064	$	(2,802	)	$	315,679	$	(6,401	)	$	674,743	$	(9,203	)



	December 31, 2016
	Less than 12 months					12 months or more					Total
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
(Dollars in thousands)	value		loss			value		loss			value		loss
U.S. Treasuries	$	97	$	(1	)	$	0	$	0		$	97	$	(1	)
Securities of U.S. Government agencies and corporations	19,917		(150		)	0		0			19,917		(150		)
Mortgage-backed securities - residential	180,654		(3,621		)	9,890		(285		)	190,544		(3,906		)
Mortgage-backed securities - commercial	123,122		(1,200		)	65,007		(1,443		)	188,129		(2,643		)
Collateralized mortgage obligations	201,305		(2,882		)	42,314		(915		)	243,619		(3,797		)
Obligations of state and other political subdivisions	94,632		(2,710		)	12,023		(150		)	106,655		(2,860		)
Asset-backed securities	116,057		(764		)	92,629		(1,249		)	208,686		(2,013		)
Other securities	7,746		(237		)	21,357		(491		)	29,103		(728		)
Total	$	743,530	$	(11,565	)	$	243,220	$	(4,533	)	$	986,750	$	(16,098	)