Investment Securities (Tables)

12 Months Ended

Dec. 31, 2017

Securities Financing Transactions Disclosures [Abstract]

Unrealized Gain (Loss) on Investments

At December 31, 2017 and 2016, amortized cost, fair value, and unrealized gains and losses on investment securities are as follows:

(Dollars in thousands)
	Amortized		Unrealized		Unrealized		Fair
December 31, 2017	Cost		Gains		Losses		Value
Available for sale securities:
U.S. Treasury and U.S. government agencies	$	40,125	$	—	$	1,395	$	38,730
Mortgage-backed U.S. government agencies		26,398		2		569		25,831
State and political subdivision obligations		27,775		7		739		27,043
Corporate debt securities		1,000		5		—		1,005
Equity securities		900		—		44		856
Total available for sale securities		96,198		14		2,747		93,465
Held to maturity securities:
U.S. Treasury and U.S. government agencies	$	10,984	$	—	$	90	$	10,894
Mortgage-backed U.S. government agencies		53,472		—		523		52,949
State and political subdivision obligations		36,900		41		301		36,640
Corporate debt securities		—		—		—		—
Equity securities		—		—		—		—
Total held to maturity securities		101,356		41		914		100,483
Total	$	197,554	$	55	$	3,661	$	193,948

(Dollars in thousands)
	Amortized		Unrealized		Unrealized		Fair
December 31, 2016	Cost		Gains		Losses		Value
Available for sale securities:
U.S. Treasury and U.S. government agencies	$	48,520	$	34	$	1,542	$	47,012
Mortgage-backed U.S. government agencies		26,181		17		579		25,619
State and political subdivision obligations		61,079		91		2,332		58,838
Corporate debt securities		1,000		—		—		1,000
Equity securities		1,268		—		112		1,156
	$	138,048	$	142	$	4,565	$	133,625

Schedule of Fair Value and Unrealized Loss on Investments in a Continuous Unrealized Loss Position

The following table presents gross unrealized losses and fair value of investments aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31, 2017 and 2016.

(Dollars in thousands)	Less Than 12 Months					12 Months or More					Total
December 31, 2017	Number of Securities	Fair Value		Unrealized Losses		Number of Securities	Fair Value		Unrealized Losses		Number of Securities	Fair Value		Unrealized Losses
Available for sale securities:
U.S. Treasury and    U.S. government agencies	3	$	5,008	$	184	18	$	33,722	$	1,211	21	$	38,730	$	1,395
Mortgage-backed    U.S. government agencies	4		5,267		75	15		20,497		494	19		25,764		569
State and political    subdivision obligations	11		6,144		102	40		19,091		637	51		25,235		739
Corporate debt securities	0		—		—	0		—		—	0		—		—
Equity securities	0		—		—	1		506		44	1		506		44
Total temporarily impaired    available for sale securities	18		16,419		361	74		73,816		2,386	92		90,235		2,747
Held to maturity securities:
U.S. Treasury and    U.S. government agencies	0	$	—	$	—	4	$	10,894	$	90	4	$	10,894	$	90
Mortgage-backed    U.S. government agencies	0		—		—	35		52,949		523	35		52,949		523
State and political    subdivision obligations	0		—		—	77		29,976		301	77		29,976		301
Corporate debt securities	0		—		—	0		—		—	0		—		—
Equity securities	0		—		—	0		—		—	0		—		—
Total temporarily impaired    held to maturity securities	0		—		—	116		93,819		914	116		93,819		914
Total	18	$	16,419	$	361	190	$	167,635	$	3,300	208	$	184,054	$	3,661
(Dollars in thousands)	Less Than 12 Months					12 Months or More					Total
December 31, 2016	Number of Securities	Fair Value		Unrealized Losses		Number of Securities	Fair Value		Unrealized Losses		Number of Securities	Fair Value		Unrealized Losses
Available for sale securities:
U.S. Treasury and    U.S. government agencies	23	$	43,698	$	1,542	0	$	—	$	—	23	$	43,698	$	1,542
Mortgage-backed    U.S. government agencies	18		24,321		579	0		—		—	18		24,321		579
State and political    subdivision obligations	108		50,582		2,332	0		—		—	108		50,582		2,332
Corporate debt securities	0		—		—	0		—		—	0		—		—
Equity securities	0		—		—	2		1,056		112	2		1,056		112
Total temporarily impaired    available for sale securities	149	$	118,601	$	4,453	2	$	1,056	$	112	151	$	119,657	$	4,565

Schedule of Gross Realized Gains (Losses) on Sales of Available-For-Sale Securities

Gross realized gains and losses on sales of available-for-sale securities for the years ended December 31, 2017, 2016, and 2015 are shown in the table below.

(Dollars in thousands)	For the year ended December 31,
	2017			2016				2015
Realized gains	$	246		$	1,927		$	325
Realized losses		(204	)		(881	)		—
Net gains	$	42		$	1,046		$	325

Investments Classified by Contractual Maturity Date

The table below is the maturity distribution of investment securities at amortized cost and fair value at December 31, 2017.

(Dollars in thousands)	Available for Sale				Held to Maturity
	Amortized		Fair		Amortized		Fair
December 31, 2017	Cost		Value		Cost		Value
Due in 1 year or less	$	100	$	100	$	2,001	$	1,989
Due after 1 year but within 5 years		12,072		11,825		9,431		9,357
Due after 5 years but within 10 years		46,307		44,779		35,941		35,679
Due after 10 years		10,771		10,424		511		509
		69,250		67,128		47,884		47,534
Mortgage-backed securities		26,398		25,831		53,472		52,949
Equity securities		550		506		—		—
	$	96,198	$	93,465	$	101,356	$	100,483