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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	$ 46,423	$ 69,637
Held to maturity, Fair Value	47,867	71,054
Held-to-maturity, Gross Unrealized Gains	1,448	1,459
Held-to-maturity, Gross Unrealized Losses	(4)	(42)
Available-for-sale, Amortized Cost	374,802	417,410
Available-for-sale, Fair Value	378,996	417,787
Available-for-sale, Gross Unrealized Gains	4,523	1,883
Available-for-sale, Gross Unrealized Losses	(329)	(1,506)
Total investment securities, Amortized Cost	421,225	487,047
Total investment securities, Fair Value	426,863	488,841
Total investment securities, Gross Unrealized Gains	5,971	3,342
Total investment securities, Gross Unrealized Losses	(333)	(1,548)
MBS pass-through securities issued by FHLMC and FNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	196,987	138,222
Available-for-sale, Fair Value	198,999	138,462
Available-for-sale, Gross Unrealized Gains	2,239	694
Available-for-sale, Gross Unrealized Losses	(227)	(454)
CMOs issued by FNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	14,885	18,266
Available-for-sale, Fair Value	15,104	18,219
Available-for-sale, Gross Unrealized Gains	219	97
Available-for-sale, Gross Unrealized Losses	0	(144)
CMOs issued by FHLMC
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	30,555	22,889
Available-for-sale, Fair Value	30,887	22,932
Available-for-sale, Gross Unrealized Gains	332	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	7,654	10,326
Available-for-sale, Fair Value	7,834	10,480
Available-for-sale, Gross Unrealized Gains	180	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	40,486	161,690
Available-for-sale, Fair Value	40,576	160,892
Available-for-sale, Gross Unrealized Gains	98	28
Available-for-sale, Gross Unrealized Losses	(8)	(826)
Privately issued CMOs
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	560	3,960
Available-for-sale, Fair Value	560	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	78,719	57,110
Available-for-sale, Fair Value	80,027	57,673
Available-for-sale, Gross Unrealized Gains	1,401	580
Available-for-sale, Gross Unrealized Losses	(93)	(17)
Corporate bonds
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available-for-sale, Amortized Cost	4,956	4,947
Available-for-sale, Fair Value	5,009	4,979
Available-for-sale, Gross Unrealized Gains	53	43
Available-for-sale, Gross Unrealized Losses	0	(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	32,765	42,919
Held to maturity, Fair Value	33,868	44,146
Held-to-maturity, Gross Unrealized Gains	1,106	1,246
Held-to-maturity, Gross Unrealized Losses	(3)	(19)
Corporate bonds
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	3,524	15,072
Held to maturity, Fair Value	3,523	15,098
Held-to-maturity, Gross Unrealized Gains	0	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	10,134	11,646
Held to maturity, Fair Value	10,476	11,810
Held-to-maturity, Gross Unrealized Gains	342	171
Held-to-maturity, Gross Unrealized Losses	$ 0	$ (7)

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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