Investment Securities - Held-to-Maturity and Available-for-Sale, Scheduled Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Securities Held-to-Maturity, Amortized Cost	$ 108,142	$ 55,564
Securities Held-to-Maturity, Gross Unrealized Gains	0	44
Securities Held-to-Maturity, Gross Unrealized Losses	(2,500)	(288)
Securities Held-to-Maturity, Fair Value	105,642	55,320
Debt Securities, Available-for-sale [Abstract]
Equity Securities Available-for-Sale, Amortized Cost		6,395
Equity Securities Available-for-Sale, Gross Unrealized Gains		667
Equity Securities Available-for-Sale, Gross Unrealized Loss		(1)
Equity Securities Available-for-Sale, Fair Value		7,061
Securities Available-for-Sale, Amortized Cost	353,228	404,766
Securities Available-for-Sale, Debt Securities, Fair Value	336,933	391,457
Securities Available-for-Sale, Gross Unrealized Gain	369	1,822
Securities Available-for-Sale, Gross Unrealized Loss	(16,664)	(8,070)
Securities Available-for-Sale, Fair Value	336,933	398,518
U.S. Government Corporations and Agencies [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Securities Held-to-Maturity, Amortized Cost, After 1 year to 5 years	6,996	6,995
Securities Held-to-Maturity, Gross Unrealized Gains, After 1 year to 5 years	0	0
Securities Held-to-Maturity, Gross Unrealized Losses, After 1 year to 5 years	(214)	(77)
Securities Held-to-Maturity, Fair Value, After 1 year to 5 years	6,782	6,918
Securities Held-to-Maturity, Amortized Cost	6,996	6,995
Securities Held-to-Maturity, Gross Unrealized Gains	0	0
Securities Held-to-Maturity, Gross Unrealized Losses	(214)	(77)
Securities Held-to-Maturity, Fair Value	6,782	6,918
Debt Securities, Available-for-sale [Abstract]
Securities Available-for-Sale, Amortized Cost, Within 1 year	15,153	1,499
Securities Available-for-Sale, Gross Unrealized Gains, Within 1 year	0	0
Securities Available-for-Sale, Gross Unrealized Losses, Within 1 year	(131)	(3)
Securities Available-for-Sale, Fair Value, Within 1 year	15,022	1,496
Securities Available-for-Sale, Amortized Cost, After 1 year to 5 years	303	15,590
Securities Available-for-Sale, Gross Unrealized Gains, After 1 year to 5 years	0	0
Securities Available-for-Sale, Gross Unrealized Losses, After 1 year to 5 years	(9)	(125)
Securities Available-for-Sale, Fair Value, After 1 year to 5 years	294	15,465
Securities Available-for-Sale, Amortized Cost	15,456	17,089
Securities Available-for-Sale, Debt Securities, Gross Unrealized Gain	0	0
Securities Available-for-Sale, Debt Securities, Gross Unrealized Losses	(140)	(128)
Securities Available-for-Sale, Debt Securities, Fair Value	15,316	16,961
State and Political Subdivisions [Member]
Debt Securities, Available-for-sale [Abstract]
Securities Available-for-Sale, Amortized Cost, Within 1 year	5,943	2,721
Securities Available-for-Sale, Gross Unrealized Gains, Within 1 year	0	1
Securities Available-for-Sale, Gross Unrealized Losses, Within 1 year	(11)	(6)
Securities Available-for-Sale, Fair Value, Within 1 year	5,932	2,716
Securities Available-for-Sale, Amortized Cost, After 1 year to 5 years	12,569	16,787
Securities Available-for-Sale, Gross Unrealized Gains, After 1 year to 5 years	15	33
Securities Available-for-Sale, Gross Unrealized Losses, After 1 year to 5 years	(97)	(44)
Securities Available-for-Sale, Fair Value, After 1 year to 5 years	12,487	16,776
Securities Available-for-Sale, Amortized Cost, After 5 years to 10 years	46,803	54,846
Securities Available-for-Sale, Gross Unrealized Gains, After 5 years to 10 years	303	897
Securities Available-for-Sale, Gross Unrealized Losses, After 5 years to 10 years	(631)	(73)
Securities Available-for-Sale, Fair Value, After 5 years to 10 years	46,475	55,670
Securities Available-for-Sale, Amortized Cost, Over 10 years	3,120	3,120
Securities Available-for-Sale, Gross Unrealized Gains, Over 10 years	0	15
Securities Available-for-Sale, Gross Unrealized Losses, Over 10 years	(122)	0
Securities Available-for-Sale, Fair Value, Over 10 years	2,998	3,135
Securities Available-for-Sale, Amortized Cost	68,435	77,474
Securities Available-for-Sale, Debt Securities, Gross Unrealized Gain	318	946
Securities Available-for-Sale, Debt Securities, Gross Unrealized Losses	(861)	(123)
Securities Available-for-Sale, Debt Securities, Fair Value	67,892	78,297
Residential Mortgage Backed Securities [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Securities Held-to-Maturity, Amortized Cost, After 5 years to 10 years	12,190	8,944
Securities Held-to-Maturity, Gross Unrealized Gains, After 5 years to 10 years	0	0
Securities Held-to-Maturity, Gross Unrecognized Losses, After 5 years to 10 years	(279)	(51)
Securities Held-to-Maturity, Fair Value, After 5 years to 10 years	11,911	8,893
Securities Held-to-Maturity, Amortized Cost, Over 10 years	88,956	39,625
Securities Held-to-Maturity, Gross Unrealized Gain, Over 10 years	0	44
Securities Held-to-Maturity, Gross Unrealized Losses, Over 10 years	(2,007)	(160)
Securities Held-to-Maturity, Fair Value, After 10 Years	86,949	39,509
Securities Held-to-Maturity, Amortized Cost	101,146	48,569
Securities Held-to-Maturity, Gross Unrealized Gains	0	44
Securities Held-to-Maturity, Gross Unrealized Losses	(2,286)	(211)
Securities Held-to-Maturity, Fair Value	98,860	48,402
Debt Securities, Available-for-sale [Abstract]
Securities Available-for-Sale, Amortized Cost, After 1 year to 5 years	4,887	3,913
Securities Available-for-Sale, Gross Unrealized Gains, After 1 year to 5 years	0	12
Securities Available-for-Sale, Gross Unrealized Losses, After 1 year to 5 years	(102)	(26)
Securities Available-for-Sale, Fair Value, After 1 year to 5 years	4,785	3,899
Securities Available-for-Sale, Amortized Cost, After 5 years to 10 years	53,041	51,428
Securities Available-for-Sale, Gross Unrealized Gains, After 5 years to 10 years	6	5
Securities Available-for-Sale, Gross Unrealized Losses, After 5 years to 10 years	(2,231)	(852)
Securities Available-for-Sale, Fair Value, After 5 years to 10 years	50,816	50,581
Securities Available-for-Sale, Amortized Cost, Over 10 years	105,808	133,237
Securities Available-for-Sale, Gross Unrealized Gains, Over 10 years	22	87
Securities Available-for-Sale, Gross Unrealized Losses, Over 10 years	(5,017)	(2,383)
Securities Available-for-Sale, Fair Value, Over 10 years	100,813	130,941
Securities Available-for-Sale, Amortized Cost	163,736	188,578
Securities Available-for-Sale, Debt Securities, Gross Unrealized Gain	28	104
Securities Available-for-Sale, Debt Securities, Gross Unrealized Losses	(7,350)	(3,261)
Securities Available-for-Sale, Debt Securities, Fair Value	156,414	185,421
Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-sale [Abstract]
Securities Available-for-Sale, Amortized Cost, After 5 years to 10 years	1,772	2,103
Securities Available-for-Sale, Gross Unrealized Gains, After 5 years to 10 years	0	0
Securities Available-for-Sale, Gross Unrealized Losses, After 5 years to 10 years	(108)	(82)
Securities Available-for-Sale, Fair Value, After 5 years to 10 years	1,664	2,021
Securities Available-for-Sale, Amortized Cost, Over 10 years	1,347	1,567
Securities Available-for-Sale, Gross Unrealized Gains, Over 10 years	0	14
Securities Available-for-Sale, Gross Unrealized Losses, Over 10 years	(30)	0
Securities Available-for-Sale, Fair Value, Over 10 years	1,317	1,581
Securities Available-for-Sale, Amortized Cost	3,119	3,670
Securities Available-for-Sale, Debt Securities, Gross Unrealized Gain	0	14
Securities Available-for-Sale, Debt Securities, Gross Unrealized Losses	(138)	(82)
Securities Available-for-Sale, Debt Securities, Fair Value	2,981	3,602
Corporate Bonds [Member]
Debt Securities, Available-for-sale [Abstract]
Securities Available-for-Sale, Amortized Cost, Within 1 year	2,506	10,006
Securities Available-for-Sale, Gross Unrealized Gains, Within 1 year	0	0
Securities Available-for-Sale, Gross Unrealized Losses, Within 1 year	(10)	(5)
Securities Available-for-Sale, Fair Value, Within 1 year	2,496	10,001
Securities Available-for-Sale, Amortized Cost, After 1 year to 5 years	23,824	24,885
Securities Available-for-Sale, Gross Unrealized Gains, After 1 year to 5 years	21	20
Securities Available-for-Sale, Gross Unrealized Losses, After 1 year to 5 years	(442)	(147)
Securities Available-for-Sale, Fair Value, After 1 year to 5 years	23,403	24,758
Securities Available-for-Sale, Amortized Cost, After 5 years to 10 years	16,152	16,669
Securities Available-for-Sale, Gross Unrealized Gains, After 5 years to 10 years	2	71
Securities Available-for-Sale, Gross Unrealized Losses, After 5 years to 10 years	(537)	(296)
Securities Available-for-Sale, Fair Value, After 5 years to 10 years	15,617	16,444
Securities Available-for-Sale, Amortized Cost, Over 10 years	60,000	60,000
Securities Available-for-Sale, Gross Unrealized Gains, Over 10 years	0	0
Securities Available-for-Sale, Gross Unrealized Losses, Over 10 years	(7,186)	(4,027)
Securities Available-for-Sale, Fair Value, Over 10 years	52,814	55,973
Securities Available-for-Sale, Amortized Cost	102,482	111,560
Securities Available-for-Sale, Debt Securities, Gross Unrealized Gain	23	91
Securities Available-for-Sale, Debt Securities, Gross Unrealized Losses	(8,175)	(4,475)
Securities Available-for-Sale, Debt Securities, Fair Value	$ 94,330	107,176
Equity Securities [Member]
Debt Securities, Available-for-sale [Abstract]
Equity Securities Available-for-Sale, Fair Value		$ 1,076