Investments - Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 20,771	$ 12,432
Gross Unrealized Gains	64	1
Gross Unrealized Losses	48	173
Estimated Fair Value	20,787	12,260
U.S. government, government agencies and authorities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	15,007	5,594
Gross Unrealized Gains	52	1
Gross Unrealized Losses	13	48
Estimated Fair Value	15,046	5,547
States, municipalities and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	604	621
Gross Unrealized Gains	1	0
Gross Unrealized Losses	4	14
Estimated Fair Value	601	607
Mortgage-backed
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,474	3,256
Gross Unrealized Gains	2	0
Gross Unrealized Losses	22	70
Estimated Fair Value	2,454	3,186
Corporate
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,686	2,961
Gross Unrealized Gains	9	0
Gross Unrealized Losses	9	41
Estimated Fair Value	$ 2,686	$ 2,920

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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-Publisher FASB
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-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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-Publisher FASB
-Name Accounting Standards Codification
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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-Publisher FASB
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