Securities - Summary of Fair Value of Available for Sale Held to Maturity (Details) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Securities available for sale [Abstract]
Amortized Cost	$ 191,835,000	$ 186,254,000
Gross unrealized gains	104,000	82,000
Gross unrealized (losses)	(3,423,000)	(3,981,000)
Securities available for sale, at fair value	188,516,087	182,354,987
Securities held to maturity [Abstract]
Amortized Cost	46,855,000	46,864,000
Gross unrealized gains	2,914,000	2,874,000
Gross unrealized (losses)		(7,000)
Estimated fair value	49,769,285	49,731,169
U. S. government agency securities
Securities available for sale [Abstract]
Amortized Cost	11,531,000	9,517,000
Gross unrealized (losses)	(217,000)	(143,000)
Securities available for sale, at fair value	11,314,000	9,374,000
State and municipal securities
Securities available for sale [Abstract]
Amortized Cost	27,781,000	28,480,000
Gross unrealized gains	101,000	65,000
Gross unrealized (losses)	(542,000)	(632,000)
Securities available for sale, at fair value	27,340,000	27,913,000
Securities held to maturity [Abstract]
Amortized Cost	36,865,000	36,842,000
Gross unrealized gains	2,818,000	2,784,000
Estimated fair value	39,683,000	39,626,000
Mortgage-backed securities
Securities available for sale [Abstract]
Amortized Cost	131,232,000	126,637,000
Gross unrealized gains	3,000	17,000
Gross unrealized (losses)	(2,097,000)	(2,059,000)
Securities available for sale, at fair value	129,138,000	124,595,000
Securities held to maturity [Abstract]
Amortized Cost	4,657,000	4,687,000
Gross unrealized gains	63,000	79,000
Estimated fair value	4,720,000	4,766,000
Asset-backed securities
Securities available for sale [Abstract]
Amortized Cost	21,291,000	21,620,000
Gross unrealized (losses)	(567,000)	(1,147,000)
Securities available for sale, at fair value	20,724,000	20,473,000
Other debt securities
Securities held to maturity [Abstract]
Amortized Cost	5,333,000	5,335,000
Gross unrealized gains	33,000	11,000
Gross unrealized (losses)		(7,000)
Estimated fair value	$ 5,366,000	$ 5,339,000

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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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 debt securities categorized neither as held-to-maturity nor trading.

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

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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