Securities (Tables)

9 Months Ended

Sep. 30, 2018

Gain (Loss) on Securities [Line Items]

Reconciliation of fair value of securities

The following table presents a summary of the amortized cost, gross unrealized gains and losses, and fair value of securities available for sale and securities held to maturity for the periods indicated:

	September 30, 2018									December 31, 2017
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(Dollars in thousands)
Available for sale securities
U.S. government agency securities	$	32,479	$	—	$	(907	)	$	31,572	$	35,475	$	86	$	(131	)	$	35,430
Agency mortgage-backed securities	213,159		874		(6,510		)	207,523		214,934		1,897		(1,067		)	215,764
Agency collateralized mortgage obligations	143,764		83		(6,202		)	137,645		124,098		78		(2,164		)	122,012
State, county, and municipal securities	1,973		8		—			1,981		2,237		37		—			2,274
Single issuer trust preferred securities issued by banks	1,000		4		—			1,004		2,012		4		—			2,016
Pooled trust preferred securities issued by banks and insurers	2,159		—		(359		)	1,800		2,179		—		(539		)	1,640
Small business administration pooled securities	55,961		—		(1,625		)	54,336		47,852		44		(118		)	47,778
Equity securities	—		—		—			—		19,432		1,594		(442		)	20,584
Total available for sale securities	$	450,495	$	969	$	(15,603	)	$	435,861	$	448,219	$	3,740	$	(4,461	)	$	447,498
Held to maturity securities
U.S. Treasury securities	$	1,004	$	2	$	—		$	1,006	$	1,006	$	29	$	—		$	1,035
Agency mortgage-backed securities	189,479		136		(5,527		)	184,088		204,768		1,791		(736		)	205,823
Agency collateralized mortgage obligations	336,346		28		(12,858		)	323,516		262,998		397		(4,987		)	258,408
Single issuer trust preferred securities issued by banks	1,500		—		(10		)	1,490		1,500		29		—			1,529
Small business administration pooled securities	25,376		—		(854		)	24,522		27,416		183		(200		)	27,399
Total held to maturity securities	$	553,705	$	166	$	(19,249	)	$	534,622	$	497,688	$	2,429	$	(5,923	)	$	494,194
Total	$	1,004,200	$	1,135	$	(34,852	)	$	970,483	$	945,907	$	6,169	$	(10,384	)	$	941,692

Schedule of contractual maturities of securities

A schedule of the contractual maturities of securities available for sale and securities held to maturity as of September 30, 2018 is presented below:

	Due in one year or less				Due after one year to five years				Due after five to ten years				Due after ten years				Total
	Amortized Cost		Fair Value		Amortized Cost		Fair Value		Amortized Cost		Fair Value		Amortized Cost		Fair Value		Amortized Cost		Fair Value
	(Dollars in thousands)
Available for sale securities
U.S. government agency securities	$	—	$	—	$	20,012	$	19,728	$	12,467	$	11,844	$	—	$	—	$	32,479	$	31,572
Agency mortgage-backed securities	278		281		44,914		43,697		99,439		96,667		68,528		66,878		213,159		207,523
Agency collateralized mortgage obligations	—		—		—		—		—		—		143,764		137,645		143,764		137,645
State, county, and municipal securities	—		—		1,022		1,023		951		958		—		—		1,973		1,981
Single issuer trust preferred securities issued by banks	—		—		—		—		—		—		1,000		1,004		1,000		1,004
Pooled trust preferred securities issued by banks and insurers	—		—		—		—		—		—		2,159		1,800		2,159		1,800
Small business administration pooled securities	—		—		—		—		—		—		55,961		54,336		55,961		54,336
Total available for sale securities	$	278	$	281	$	65,948	$	64,448	$	112,857	$	109,469	$	271,412	$	261,663	$	450,495	$	435,861
Held to maturity securities
U.S. Treasury securities	$	—	$	—	$	1,004	$	1,006	$	—	$	—	$	—	$	—	$	1,004	$	1,006
Agency mortgage-backed securities	—		—		12,442		12,191		37,473		36,481		139,564		135,416		189,479		184,088
Agency collateralized mortgage obligations	—		—		—		—		941		936		335,405		322,580		336,346		323,516
Single issuer trust preferred securities issued by banks	—		—		—		—		1,500		1,490		—		—		1,500		1,490
Small business administration pooled securities	—		—		—		—		—		—		25,376		24,522		25,376		24,522
Total held to maturity securities	$	—	$	—	$	13,446	$	13,197	$	39,914	$	38,907	$	500,345	$	482,518	$	553,705	$	534,622

Schedule of gross unrealized losses and fair value of investments

The following tables show the gross unrealized losses and fair value of the Company’s investments in an unrealized loss position, which the Company has not deemed to be OTTI, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position:

	September 30, 2018
		Less than 12 months					12 months or longer					Total
	# of holdings	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(Dollars in thousands)
U.S. government agency securities	3	$	31,572	$	(907	)	$	—	$	—		$	31,572	$	(907	)
Agency mortgage-backed securities	154	284,810		(8,375		)	77,412		(3,662		)	362,222		(12,037		)
Agency collateralized mortgage obligations	57	294,626		(8,847		)	154,168		(10,213		)	448,794		(19,060		)
Single issuer trust preferred securities issued by banks and insurers	1	1,490		(10		)	—		—			1,490		(10		)
Pooled trust preferred securities issued by banks and insurers	1	—		—			1,800		(359		)	1,800		(359		)
Small business administration pooled securities	8	38,264		(685		)	40,594		(1,794		)	78,858		(2,479		)
Total temporarily impaired securities	224	$	650,762	$	(18,824	)	$	273,974	$	(16,028	)	$	924,736	$	(34,852	)

	December 31, 2017
		Less than 12 months					12 months or longer					Total
	# of holdings	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(Dollars in thousands)
U.S.government agency securities	4	$	24,343	$	(131	)	$	—	$	—		$	24,343	$	(131	)
Agency mortgage-backed securities	84	235,411		(1,493		)	14,886		(310		)	250,297		(1,803		)
Agency collateralized mortgage obligations	42	178,142		(1,579		)	159,506		(5,572		)	337,648		(7,151		)
Pooled trust preferred securities issued by banks and insurers	1	—		—			1,640		(539		)	1,640		(539		)
Small business administration pooled securities	4	34,553		(223		)	9,647		(95		)	44,200		(318		)
Equity securities	28	3,290		(39		)	7,619		(403		)	10,909		(442		)
Total temporarily impaired securities	163	$	475,739	$	(3,465	)	$	193,298	$	(6,919	)	$	669,037	$	(10,384	)