Securities - Summary of Fair Value of Available for Sale Held to Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Securities available for sale [Abstract]
Amortized Cost	$ 233,673	$ 247,042
Gross unrealized gains	2,567	1,616
Gross unrealized (losses)	(2,549)	(4,850)
Estimated fair value	233,691	243,808
Securities held to maturity [Abstract]
Amortized Cost	3,727	3,734
Gross unrealized gains	79	54
Gross unrealized (losses)		(3)
Estimated fair value	3,806	3,785
U. S. government agency securities
Securities available for sale [Abstract]
Amortized Cost	10,785	11,053
Gross unrealized (losses)	(184)	(347)
Estimated fair value	10,601	10,706
State and municipal securities
Securities available for sale [Abstract]
Amortized Cost	62,267	62,142
Gross unrealized gains	1,436	765
Gross unrealized (losses)	(303)	(981)
Estimated fair value	63,400	61,926
Securities held to maturity [Abstract]
Amortized Cost	3,727	3,734
Gross unrealized gains	79	54
Gross unrealized (losses)		(3)
Estimated fair value	3,806	3,785
Mortgage-backed securities
Securities available for sale [Abstract]
Amortized Cost	138,851	146,547
Gross unrealized gains	1,080	776
Gross unrealized (losses)	(1,798)	(3,165)
Estimated fair value	138,133	144,158
Asset-backed securities
Securities available for sale [Abstract]
Amortized Cost	9,912	15,437
Gross unrealized gains		4
Gross unrealized (losses)	(164)	(157)
Estimated fair value	9,748	15,284
Other debt securities
Securities available for sale [Abstract]
Amortized Cost	11,858	11,863
Gross unrealized gains	51	71
Gross unrealized (losses)	(100)	(200)
Estimated fair value	$ 11,809	$ 11,734

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (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 investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Amount, before other-than-temporary impairment (OTTI) accretion, of investment in debt securities measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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