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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	$ 94,475	$ 116,437
Held to maturity, Fair Value	96,017	118,643
Held-to-maturity, Gross Unrealized Gains	1,614	2,271
Held-to-maturity, Gross Unrealized Losses	(72)	(65)
Available-for-sale, Amortized Cost	252,709	199,045
Available-for-sale, Fair Value	254,018	200,848
Available-for-sale, Gross Unrealized Gains	1,830	2,234
Available-for-sale, Gross Unrealized Losses	(521)	(431)
Total investment securities, Amortized Cost	347,184	315,482
Total investment securities, Fair Value	350,035	319,491
Total investment securities, Gross Unrealized Gains	3,444	4,505
Total investment securities, Gross Unrealized Losses	(593)	(496)
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	120,719	92,963
Available-for-sale, Fair Value	121,273	94,214
Available-for-sale, Gross Unrealized Gains	748	1,262
Available-for-sale, Gross Unrealized Losses	(194)	(11)
CMOs issued by FNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	12,993	14,771
Available-for-sale, Fair Value	13,106	14,790
Available-for-sale, Gross Unrealized Gains	150	77
Available-for-sale, Gross Unrealized Losses	(37)	(58)
CMOs issued by FHLMC
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	27,065	31,238
Available-for-sale, Fair Value	27,191	31,260
Available-for-sale, Gross Unrealized Gains	164	109
Available-for-sale, Gross Unrealized Losses	(38)	(87)
CMOs issued by GNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	13,950	17,573
Available-for-sale, Fair Value	14,216	17,855
Available-for-sale, Gross Unrealized Gains	274	298
Available-for-sale, Gross Unrealized Losses	(8)	(16)
Debentures of government sponsored agencies
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	31,121	14,694
Available-for-sale, Fair Value	31,072	14,557
Available-for-sale, Gross Unrealized Gains	98	95
Available-for-sale, Gross Unrealized Losses	(147)	(232)
Privately-issued CMOs
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	5,011	7,137
Available-for-sale, Fair Value	5,209	7,294
Available-for-sale, Gross Unrealized Gains	200	172
Available-for-sale, Gross Unrealized Losses	(2)	(15)
Obligations of state and political subdivisions
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	36,909	15,733
Available-for-sale, Fair Value	36,937	15,880
Available-for-sale, Gross Unrealized Gains	123	155
Available-for-sale, Gross Unrealized Losses	(95)	(8)
Corporate bonds
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	4,941	4,936
Available-for-sale, Fair Value	5,014	4,998
Available-for-sale, Gross Unrealized Gains	73	66
Available-for-sale, Gross Unrealized Losses	0	(4)
Obligations of state and political subdivisions
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	54,183	63,425
Held to maturity, Fair Value	55,455	65,121
Held-to-maturity, Gross Unrealized Gains	1,332	1,736
Held-to-maturity, Gross Unrealized Losses	(60)	(40)
Corporate bonds
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	27,615	40,257
Held to maturity, Fair Value	27,732	40,448
Held-to-maturity, Gross Unrealized Gains	122	216
Held-to-maturity, Gross Unrealized Losses	(5)	(25)
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	12,677	12,755
Held to maturity, Fair Value	12,830	13,074
Held-to-maturity, Gross Unrealized Gains	160	319
Held-to-maturity, Gross Unrealized Losses	$ (7)	$ 0

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