Investments - Investment Summary (Details) - Level 2 - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Held-to-maturity Securities [Line Items]
Amortized Costs	$ 19,279	$ 18,558
Gross Unrealized Gains	910	426
Gross Unrealized Losses	(4)	(5)
Fair Value	20,185	18,979
U.S. Treasury bills
Schedule of Held-to-maturity Securities [Line Items]
Amortized Costs	10,785	10,784
Gross Unrealized Gains	568	270
Gross Unrealized Losses	0	0
Fair Value	11,353	11,054
Corporate bonds
Schedule of Held-to-maturity Securities [Line Items]
Amortized Costs	1,705	1,705
Gross Unrealized Gains	67	70
Gross Unrealized Losses	0	0
Fair Value	1,772	1,775
Collateralized mortgage obligations
Schedule of Held-to-maturity Securities [Line Items]
Amortized Costs	6,192	5,472
Gross Unrealized Gains	233	56
Gross Unrealized Losses	(4)	(5)
Fair Value	6,421	5,523
Yankees
Schedule of Held-to-maturity Securities [Line Items]
Amortized Costs	597	597
Gross Unrealized Gains	42	30
Gross Unrealized Losses	0	0
Fair Value	$ 639	$ 627

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

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-Publisher FASB
-Name Accounting Standards Codification
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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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