Investment Securities (Tables)

12 Months Ended

Dec. 31, 2017

Investments, Debt and Equity Securities [Abstract]

Reconciliation of Available-for-Sale Securities

The amortized cost, gross unrealized gains and losses, and the fair value of the Company’s available for sale and held to maturity investment securities are as follows:

	December 31, 2017									December 31, 2016
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
AVAILABLE FOR SALE
U.S. Treasury and U.S. government agencies	$	148,968	$	78	$	(1,791	)	$	147,255	$	118,537	$	102	$	(1,280	)	$	117,359
Mortgage-backed securities, residential	419,538		479		(5,763		)	414,254		406,851		1,174		(4,487		)	403,538
Mortgage-backed securities, multifamily	10,133		7		(63		)	10,077		10,192		30		(35		)	10,187
Obligations of states and political subdivisions	51,289		448		(417		)	51,320		48,868		391		(933		)	48,326
Debt securities	5,000		140		—			5,140		5,350		63		(1		)	5,412
Equity securities	15,545		3,000		(456		)	18,089		17,314		5,000		(432		)	21,882
	$	650,473	$	4,152	$	(8,490	)	$	646,135	$	607,112	$	6,760	$	(7,168	)	$	606,704

Reconciliation of Held-to-Maturity Securities

	December 31, 2017									December 31, 2016
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
HELD TO MATURITY
U.S. government agencies	$	33,415	$	24	$	(402	)	$	33,037	$	33,553	$	144	$	(430	)	$	33,267
Mortgage-backed securities, residential	54,991		249		(978		)	54,262		38,706		369		(598		)	38,477
Mortgage-backed securities, multifamily	1,957		—		(22		)	1,935		2,059		—		(44		)	2,015
Obligations of states and political subdivisions	43,318		306		(188		)	43,436		71,284		269		(385		)	71,168
Debt securities	6,004		14		—			6,018		2,012		51		—			2,063
	$	139,685	$	593	$	(1,590	)	$	138,688	$	147,614	$	833	$	(1,457	)	$	146,990

Summary of Contractual Maturities of Investment Securities Classified as Available for Sale and Held to Maturity

The following table lists contractual maturities of investment securities classified as available for sale and held to maturity. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties.

	Available for Sale				Held to Maturity
	Amortized		Fair		Amortized		Fair
December 31, 2017	Cost		Value		Cost		Value
	(in thousands)
Due in one year or less	$	9,387	$	9,387	$	16,385	$	16,401
Due after one year through five years	109,655		108,999		38,986		38,903
Due after five years through ten years	56,380		55,577		23,568		23,392
Due after ten years	29,835		29,752		3,798		3,795
	205,257		203,715		82,737		82,491
Mortgage-backed securities	429,671		424,331		56,948		56,197
Equity securities	15,545		18,089		—		—
Total securities	$	650,473	$	646,135	$	139,685	$	138,688

Sales of Securities, Gross Gains and Gross Losses on Sales of Securities

The following table shows proceeds from sales of securities, gross gains and gross losses on sales and calls of securities for the periods indicated:

	Years Ended December 31,
	2017			2016		2015
	(in thousands)
Sale proceeds	$	4,500		$	15,654	$	33,613
Gross gains	2,539			370		304
Gross losses	(15		)	—		(63		)

Reconciliation of Available-for-Sale and Held-to-Maturity Securities in Continuous Unrealized Loss Position

The following table indicates the length of time individual securities have been in a continuous unrealized loss position at December 31, 2017 and 2016:

December 31, 2017	Less than 12 Months				12 Months or Longer				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Number of Securities	Fair Value		Unrealized Losses
	(dollars in thousands)
AVAILABLE FOR SALE
U.S. Treasury and U.S. government agencies	$	80,391	$	646	$	54,769	$	1,145	27	$	135,160	$	1,791
Mortgage-backed securities, residential	199,387		1,723		157,739		4,040		118	357,126		5,763
Mortgage-backed securities, multifamily	—		—		5,088		63		1	5,088		63
Obligations of states and political subdivisions	9,612		77		12,970		340		39	22,582		417
Equity securities	—		—		9,657		456		2	9,657		456
	$	289,390	$	2,446	$	240,223	$	6,044	187	$	529,613	$	8,490
HELD TO MATURITY
U.S. government agencies	$	15,371	$	95	$	6,720	$	307	4	$	22,091	$	402
Mortgage-backed securities, residential	26,090		426		19,203		552		25	45,293		978
Mortgage-backed securities, multifamily	1,935		22		—		—		2	1,935		22
Obligations of states and political subdivisions	15,353		56		6,028		132		23	21,381		188
	$	58,749	$	599	$	31,951	$	991	54	$	90,700	$	1,590

December 31, 2016	Less than 12 Months				12 Months or Longer				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Number of securities	Fair Value		Unrealized Losses
	(dollars in thousands)
AVAILABLE FOR SALE
U.S. Treasury and U.S. government agencies	$	94,153	$	1,280	$	—	$	—	18	$	94,153	$	1,280
Mortgage-backed securities, residential	292,873		4,078		15,453		409		91	308,326		4,487
Mortgage-backed securities, multifamily	5,178		35		—		—		1	5,178		35
Obligations of states and political subdivisions	29,904		933		—		—		54	29,904		933
Debt securities	350		1		—		—		1	350		1
Equity securities	6,030		94		4,720		338		2	10,750		432
	$	428,488	$	6,421	$	20,173	$	747	167	$	448,661	$	7,168
HELD TO MATURITY
U.S. government agencies	$	17,147	$	430	$	—	$	—	3	$	17,147	$	430
Mortgage-backed securities, residential	27,909		535		1,061		63		15	28,970		598
Mortgage-backed securities, multifamily	2,015		44		—		—		2	2,015		44
Obligations of states and political subdivisions	50,302		384		401		1		43	50,703		385
	$	97,373	$	1,393	$	1,462	$	64	63	$	98,835	$	1,457