Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	$ 69,637	$ 116,437
Held-to-maturity, Fair Value	71,054	118,643
Held-to-maturity, Gross Unrealized Gains	1,459	2,271
Held-to-maturity, Gross Unrealized (Losses)	(42)	(65)
Available for sale, Amortized Cost	417,410	199,045
Available for sale, Fair Value	417,787	200,848
Available-for-sale, Gross Unrealized Gains	1,883	2,234
Available-for-sale, Gross Unrealized (Losses)	(1,506)	(431)
Total investment securities, Amortized Cost	487,047	315,482
Total investment securities, Fair Value	488,841	319,491
Total investment securities, Gross Unrealized Gains	3,342	4,505
Total investment securities, Gross Unrealized (Losses)	(1,548)	(496)
MBS pass-through securities
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for sale, Amortized Cost	138,222	92,963
Available for sale, Fair Value	138,462	94,214
Available-for-sale, Gross Unrealized Gains	694	1,262
Available-for-sale, Gross Unrealized (Losses)	(454)	(11)
CMOs issued by FNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for sale, Amortized Cost	18,266	14,771
Available for sale, Fair Value	18,219	14,790
Available-for-sale, Gross Unrealized Gains	97	77
Available-for-sale, Gross Unrealized (Losses)	(144)	(58)
CMOs issued by FHLMC
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for sale, Amortized Cost	22,889	31,238
Available for sale, Fair Value	22,932	31,260
Available-for-sale, Gross Unrealized Gains	82	109
Available-for-sale, Gross Unrealized (Losses)	(39)	(87)
CMOs issued by GNMA
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for sale, Amortized Cost	10,326	17,573
Available for sale, Fair Value	10,480	17,855
Available-for-sale, Gross Unrealized Gains	169	298
Available-for-sale, Gross Unrealized (Losses)	(15)	(16)
Debentures of government-sponsored agencies
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for sale, Amortized Cost	161,690	14,694
Available for sale, Fair Value	160,892	14,557
Available-for-sale, Gross Unrealized Gains	28	95
Available-for-sale, Gross Unrealized (Losses)	(826)	(232)
Privately-issued CMOs
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for sale, Amortized Cost	3,960	7,137
Available for sale, Fair Value	4,150	7,294
Available-for-sale, Gross Unrealized Gains	190	172
Available-for-sale, Gross Unrealized (Losses)	0	(15)
Obligations of state and political subdivisions
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	42,919	63,425
Held-to-maturity, Fair Value	44,146	65,121
Held-to-maturity, Gross Unrealized Gains	1,246	1,736
Held-to-maturity, Gross Unrealized (Losses)	(19)	(40)
Available for sale, Amortized Cost	57,110	15,733
Available for sale, Fair Value	57,673	15,880
Available-for-sale, Gross Unrealized Gains	580	155
Available-for-sale, Gross Unrealized (Losses)	(17)	(8)
Corporate bonds
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	15,072	40,257
Held-to-maturity, Fair Value	15,098	40,448
Held-to-maturity, Gross Unrealized Gains	42	216
Held-to-maturity, Gross Unrealized (Losses)	(16)	(25)
Available for sale, Amortized Cost	4,947	4,936
Available for sale, Fair Value	4,979	4,998
Available-for-sale, Gross Unrealized Gains	43	66
Available-for-sale, Gross Unrealized (Losses)	(11)	(4)
MBS pass-through securities
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Held to maturity, Amortized Cost	11,646	12,755
Held-to-maturity, Fair Value	11,810	13,074
Held-to-maturity, Gross Unrealized Gains	171	319
Held-to-maturity, Gross Unrealized (Losses)	$ (7)	$ 0

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Fair Value of Available-for-sale Securities and Held-to-maturity Securities.

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

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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