Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Amortized cost and fair values of securities
Total Fair value	$ 83,240	$ 88,179
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost	69,519
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value	69,522
Amortized Cost	82,863	87,808
Gross Unrealized Gains	409	411
Gross Unrealized Losses	(32)	(40)
Certificates of Deposit [Member]
Amortized cost and fair values of securities
Total Fair value	69,011	73,507
Amortized Cost	69,011	73,507
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Municipal Bonds [Member]
Amortized cost and fair values of securities
Total Fair value	511	509
Available-for-sale Securities, Amortized Cost Basis	508	509
Equity mutual fund [Member]
Amortized cost and fair values of securities
Total Fair value	0	0
Mortgage - backed securities - residential [Member]
Amortized cost and fair values of securities
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Amortized Cost	9,828
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	10,207
Total Fair value	10,207	10,478
Amortized Cost	9,828	10,116
Gross Unrealized Gains	401	400
Gross Unrealized Losses	(22)	(38)
Collateralized mortgage obligations - residential [Member]
Amortized cost and fair values of securities
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Amortized Cost	3,516
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	3,511
Total Fair value	3,511	3,685
Amortized Cost	3,516	3,676
Gross Unrealized Gains	5	11
Gross Unrealized Losses	(10)	(2)
Common Class B [Member] \| Equity mutual fund [Member]
Amortized cost and fair values of securities
Total Fair value		3,427
Amortized Cost		0
Gross Unrealized Gains		3,427
Gross Unrealized Losses		0
Fair Value, Measurements, Nonrecurring [Member]
Amortized cost and fair values of securities
Total Fair value	83,240	88,179
Fair Value, Measurements, Nonrecurring [Member] \| Certificates of Deposit [Member]
Amortized cost and fair values of securities
Total Fair value	69,011	73,507
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Amortized cost and fair values of securities
Total Fair value	83,240	$ 88,179
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Certificates of Deposit [Member]
Amortized cost and fair values of securities
Total Fair value	$ 69,011

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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