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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	$ 86,471	$ 116,437
Held to maturity, Fair Value	88,104	118,643
Held-to-maturity, Gross Unrealized Gains	1,648	2,271
Held-to-maturity, Gross Unrealized Losses	(15)	(65)
Available-for-sale, Amortized Cost	331,024	199,045
Available-for-sale, Fair Value	333,856	200,848
Available-for-sale, Gross Unrealized Gains	3,018	2,234
Available-for-sale, Gross Unrealized Losses	(186)	(431)
Total investment securities, Amortized Cost	417,495	315,482
Total investment securities, Fair Value	421,960	319,491
Total investment securities, Gross Unrealized Gains	4,666	4,505
Total investment securities, Gross Unrealized Losses	(201)	(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	116,513	92,963
Available-for-sale, Fair Value	117,963	94,214
Available-for-sale, Gross Unrealized Gains	1,488	1,262
Available-for-sale, Gross Unrealized Losses	(38)	(11)
CMOs issued by FNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	16,211	14,771
Available-for-sale, Fair Value	16,385	14,790
Available-for-sale, Gross Unrealized Gains	208	77
Available-for-sale, Gross Unrealized Losses	(34)	(58)
CMOs issued by FHLMC
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	24,645	31,238
Available-for-sale, Fair Value	24,869	31,260
Available-for-sale, Gross Unrealized Gains	239	109
Available-for-sale, Gross Unrealized Losses	(15)	(87)
CMOs issued by GNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	11,951	17,573
Available-for-sale, Fair Value	12,200	17,855
Available-for-sale, Gross Unrealized Gains	254	298
Available-for-sale, Gross Unrealized Losses	(5)	(16)
Debentures of government sponsored agencies
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	101,987	14,694
Available-for-sale, Fair Value	102,165	14,557
Available-for-sale, Gross Unrealized Gains	229	95
Available-for-sale, Gross Unrealized Losses	(51)	(232)
Privately-issued CMOs
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	4,700	7,137
Available-for-sale, Fair Value	4,891	7,294
Available-for-sale, Gross Unrealized Gains	193	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	50,073	15,733
Available-for-sale, Fair Value	50,377	15,880
Available-for-sale, Gross Unrealized Gains	345	155
Available-for-sale, Gross Unrealized Losses	(41)	(8)
Corporate bonds
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	4,944	4,936
Available-for-sale, Fair Value	5,006	4,998
Available-for-sale, Gross Unrealized Gains	62	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	50,570	63,425
Held to maturity, Fair Value	51,867	65,121
Held-to-maturity, Gross Unrealized Gains	1,302	1,736
Held-to-maturity, Gross Unrealized Losses	(5)	(40)
Corporate bonds
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	23,578	40,257
Held to maturity, Fair Value	23,662	40,448
Held-to-maturity, Gross Unrealized Gains	87	216
Held-to-maturity, Gross Unrealized Losses	(3)	(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	12,323	12,755
Held to maturity, Fair Value	12,575	13,074
Held-to-maturity, Gross Unrealized Gains	259	319
Held-to-maturity, Gross Unrealized Losses	$ (7)	$ 0

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