Securities - Reconciliation from Amortized Cost to Estimated Fair Value of Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available for sale:
Amortized cost	$ 63,883	$ 47,762
Gross unrealized gains	780	201
Gross unrealized losses	(388)	(1,250)
Estimated fair value	64,275	46,713
Held to maturity:
Amortized cost	0	14,875
Gross unrealized gains	0	211
Gross unrealized losses	0	(284)
Estimated fair value	0	14,802
Equity securities:
Amortized cost	2,218	2,394
Gross unrealized gains	142	0
Gross unrealized losses	(71)	(250)
Estimated fair value	2,289	2,144
U.S. Government sponsored entities
Available for sale:
Amortized cost	5,751	5,758
Gross unrealized gains	4	0
Gross unrealized losses	(2)	(116)
Estimated fair value	5,753	5,642
Held to maturity:
Amortized cost	0	2,527
Gross unrealized gains	0	0
Gross unrealized losses	0	(94)
Estimated fair value	0	2,433
State and political subdivisions
Available for sale:
Amortized cost	4,992	4,614
Gross unrealized gains	174	4
Gross unrealized losses	(12)	(120)
Estimated fair value	5,154	4,498
Held to maturity:
Amortized cost	0	951
Gross unrealized gains	0	110
Gross unrealized losses	0	0
Estimated fair value	0	1,061
Residential mortgage-backed securities
Available for sale:
Amortized cost	27,698	27,159
Gross unrealized gains	372	74
Gross unrealized losses	(106)	(620)
Estimated fair value	27,964	26,613
Held to maturity:
Amortized cost	0	3,312
Gross unrealized gains	0	17
Gross unrealized losses	0	(52)
Estimated fair value	0	3,277
Commercial mortgage-backed securities
Held to maturity:
Amortized cost	0	3,570
Gross unrealized gains	0	0
Gross unrealized losses	0	(138)
Estimated fair value	0	3,432
Corporate and other securities
Available for sale:
Amortized cost	25,442	10,231
Gross unrealized gains	230	123
Gross unrealized losses	(268)	(394)
Estimated fair value	25,404	9,960
Held to maturity:
Amortized cost	0	4,515
Gross unrealized gains	0	84
Gross unrealized losses	0	0
Estimated fair value	$ 0	$ 4,599

Equity Securities, FV-NI, Accumulated Unrecognized Holding Gain

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Equity Securities, FV-NI, Accumulated Unrecognized Holding Loss

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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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Amount, before tax, of unrealized loss 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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