Securities Available-for-Sale (Tables)

12 Months Ended

Dec. 31, 2016

Investments, Debt and Equity Securities [Abstract]

Composition of Securities Available-for-Sale

The following tables present the amortized cost and fair value of available-for-sale securities as of the dates presented:

	December 31, 2016									December 31, 2015
(dollars in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
U.S. Treasury securities	$	24,891	$	47	$	(127	)	$	24,811	$	14,914	$	27	$	—		$	14,941
Obligations of U.S. government corporations and agencies	230,989		1,573		(383		)	232,179		262,045		1,825		(567		)	263,303
Collateralized mortgage obligations of U.S. government corporations and agencies	130,046		465		(734		)	129,777		128,458		693		(316		)	128,835
Residential mortgage-backed securities of U.S. government corporations and agencies	36,606		984		(232		)	37,358		39,185		1,091		(151		)	40,125
Commercial mortgage-backed securities of U.S. government corporations and agencies	127,311		243		(1,950		)	125,604		69,697		183		(676		)	69,204
Obligations of states and political subdivisions	128,783		3,772		(46		)	132,509		128,904		5,988		(6		)	134,886
Debt Securities	678,626		7,084		(3,472		)	682,238		643,203		9,807		(1,716		)	651,294
Marketable equity securities	7,579		3,670		—			11,249		7,579		2,090		—			9,669
Total	$	686,205	$	10,754	$	(3,472	)	$	693,487	$	650,782	$	11,897	$	(1,716	)	$	660,963

Schedule of Gross and Net Realized Gains and Losses on Sale of Securities

The following table shows the composition of gross and net realized gains and losses for the periods presented:

	Years ended December 31,
(dollars in thousands)	2016		2015			2014
Gross realized gains	$	—	$	—		$	41
Gross realized losses	—		(34		)	—
Net Realized (Losses) Gains	$	—	$	(34	)	$	41

Fair Value and Age of Gross Unrealized Losses by Investment Category

The following tables present the fair value and the age of gross unrealized losses by investment category as of the dates presented:

	December 31, 2016
	Less Than 12 Months						12 Months or More						Total
(dollars in thousands)	Number of Securities	Fair Value		Unrealized Losses			Number of Securities	Fair Value		Unrealized Losses		Number of Securities	Fair Value		Unrealized Losses
U.S. Treasury securities	1	$	9,811	$	(127	)	—	$	—	$	—	1	$	9,811	$	(127	)
Obligations of U.S. government corporations and agencies	7	62,483		(383		)	—	—		—		7	62,483		(383		)
Collateralized mortgage obligations of U.S. government corporations and agencies	10	83,031		(734		)	—	—		—		10	83,031		(734		)
Residential mortgage-backed securities of U.S. government corporations and agencies	2	10,022		(232		)	—	—		—		2	10,022		(232		)
Commercial mortgage-backed securities of U.S. government corporations and agencies	10	96,576		(1,950		)	—	—		—		10	96,576		(1,950		)
Obligations of states and political subdivisions	1	5,577		(46		)	—	—		—		1	5,577		(46		)
Debt Securities	31	267,500		(3,472		)	—	—		—		31	267,500		(3,472		)
Marketable equity securities	—	—		—			—	—		—		—	—		—
Total Temporarily Impaired Securities	31	$	267,500	$	(3,472	)	—	$	—	$	—	31	$	267,500	$	(3,472	)

	December 31, 2015
	Less Than 12 Months						12 Months or More							Total
(dollars in thousands)	Number of Securities	Fair  Value		Unrealized Losses			Number of Securities	Fair Value		Unrealized Losses			Number of Securities	Fair Value		Unrealized Losses
U.S. Treasury securities	—	$	—	$	—		—	$	—	$	—		—	$	—	$	—
Obligations of U.S. government corporations and agencies	10	88,584		(379		)	2	14,542		(188		)	12	103,126		(567		)
Collateralized mortgage obligations of U.S. government corporations and agencies	6	61,211		(316		)	—	—		—			6	61,211		(316		)
Residential mortgage-backed securities of U.S. government corporations and agencies	1	7,993		(151		)	—	—		—			1	7,993		(151		)
Commercial mortgage-backed securities of U.S. government corporations and agencies	5	50,839		(450		)	1	9,472		(226		)	6	60,311		(676		)
Obligations of states and political subdivisions	1	5,370		(6		)	—	—		—			1	5,370		(6		)
Debt Securities	23	213,997		(1,302		)	3	24,014		(414		)	26	238,011		(1,716		)
Marketable equity securities	—	—		—			—	—		—			—	—		—
Total Temporarily Impaired Securities	23	$	213,997	$	(1,302	)	3	$	24,014	$	(414	)	26	$	238,011	$	(1,716	)

Unrealized Gain (Loss) on Investments

The following table displays net unrealized gains and losses, net of tax, on securities available-for-sale included in accumulated other comprehensive income/(loss), for the periods presented:

	December 31, 2016									December 31, 2015
(dollars in thousands)	Gross Unrealized Gains			Gross Unrealized Losses			Net Unrealized Gains (Losses)			Gross Unrealized Gains			Gross Unrealized Losses			Net Unrealized Gains (Losses)
Total unrealized gains (losses) on securities available for sale	$	10,754		$	(3,472	)	$	7,282		$	11,897		$	(1,716	)	$	10,181
Income tax (expense) benefit	(3,776		)	1,219			(2,557		)	(4,164		)	601			(3,563		)
Net unrealized gains (losses), net of tax included in accumulated other comprehensive income(loss)	$	6,978		$	(2,253	)	$	4,725		$	7,733		$	(1,115	)	$	6,618

Amortized Cost and Fair Value of Available-for-Sale Securities

The amortized cost and fair value of securities available-for-sale at December 31, 2016 by contractual maturity are included in the table below. Actual maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties.

	December 31, 2016
(dollars in thousands)	Amortized Cost		Fair Value
Due in one year or less	$	52,594	$	52,696
Due after one year through five years	201,450		203,513
Due after five years through ten years	64,569		64,975
Due after ten years	66,050		68,315
	384,663		389,499
Collateralized mortgage obligations of U.S. government corporations and agencies	130,046		129,777
Residential mortgage-backed securities of U.S. government corporations and agencies	36,606		37,358
Commercial mortgage-backed securities of U.S. government corporations and agencies	127,311		125,604
Debt Securities	678,626		682,238
Marketable equity securities	7,579		11,249
Total	$	686,205	$	693,487