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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	$ 58,491	$ 69,637
Held to maturity, Fair Value	60,160	71,054
Held-to-maturity, Gross Unrealized Gains	1,678	1,459
Held-to-maturity, Gross Unrealized Losses	(9)	(42)
Available-for-sale, Amortized Cost	318,336	417,410
Available-for-sale, Fair Value	323,361	417,787
Available-for-sale, Gross Unrealized Gains	5,037	1,883
Available-for-sale, Gross Unrealized Losses	(12)	(1,506)
Total investment securities, Amortized Cost	376,827	487,047
Total investment securities, Fair Value	383,521	488,841
Total investment securities, Gross Unrealized Gains	6,715	3,342
Total investment securities, Gross Unrealized Losses	(21)	(1,548)
Mortgage-backed Securities, Issued by FHLMC and FNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	111,682	138,222
Available-for-sale, Fair Value	113,877	138,462
Available-for-sale, Gross Unrealized Gains	2,195	694
Available-for-sale, Gross Unrealized Losses	0	(454)
CMOs issued by FNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	23,061	18,266
Available-for-sale, Fair Value	23,387	18,219
Available-for-sale, Gross Unrealized Gains	331	97
Available-for-sale, Gross Unrealized Losses	(5)	(144)
CMOs issued by FHLMC
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	21,110	22,889
Available-for-sale, Fair Value	21,451	22,932
Available-for-sale, Gross Unrealized Gains	341	82
Available-for-sale, Gross Unrealized Losses	0	(39)
CMOs issued by GNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	8,470	10,326
Available-for-sale, Fair Value	8,692	10,480
Available-for-sale, Gross Unrealized Gains	222	169
Available-for-sale, Gross Unrealized Losses	0	(15)
Debentures of government sponsored agencies
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	83,566	161,690
Available-for-sale, Fair Value	83,758	160,892
Available-for-sale, Gross Unrealized Gains	193	28
Available-for-sale, Gross Unrealized Losses	(1)	(826)
Privately issued CMOs
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	768	3,960
Available-for-sale, Fair Value	768	4,150
Available-for-sale, Gross Unrealized Gains	1	190
Available-for-sale, Gross Unrealized Losses	(1)	0
Obligations of state and political subdivisions
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	64,725	57,110
Available-for-sale, Fair Value	66,452	57,673
Available-for-sale, Gross Unrealized Gains	1,729	580
Available-for-sale, Gross Unrealized Losses	(2)	(17)
Corporate bonds
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	4,954	4,947
Available-for-sale, Fair Value	4,976	4,979
Available-for-sale, Gross Unrealized Gains	25	43
Available-for-sale, Gross Unrealized Losses	(3)	(11)
Obligations of state and political subdivisions
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	39,009	42,919
Held to maturity, Fair Value	40,337	44,146
Held-to-maturity, Gross Unrealized Gains	1,336	1,246
Held-to-maturity, Gross Unrealized Losses	(8)	(19)
Corporate bonds
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	8,529	15,072
Held to maturity, Fair Value	8,534	15,098
Held-to-maturity, Gross Unrealized Gains	6	42
Held-to-maturity, Gross Unrealized Losses	(1)	(16)
MBS pass-through securities issued by FHLMC and FNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	10,953	11,646
Held to maturity, Fair Value	11,289	11,810
Held-to-maturity, Gross Unrealized Gains	336	171
Held-to-maturity, Gross Unrealized Losses	$ 0	$ (7)

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