Available-for-Sale Securities - Summary of Maturities of Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Schedule Of Available For Sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	$ 52,037	$ 27,569
Available-for-sale securities, at fair value (Note 3)	51,966	27,144
U.S. Government and Federal Agencies
Schedule Of Available For Sale Securities [Line Items]
Available-for-Sale Securities Three months or less, Amortized Cost	34,515	4,997
Available-for-Sale Securities After three months through one year, Amortized Cost	12,875	4,554
Available-for-Sale Securities After one year through five years, Amortized Cost	3,497	16,370
Available-for-Sale Securities, Amortized Cost	50,887	25,921
Available-for-Sale Securities Three months or less, Fair Value	34,505	4,995
Available-for-Sale Securities After three months through one year, Fair Value	12,819	4,497
Available-for-Sale Securities After one year through five years, Fair Value	3,484	16,018
Available-for-sale securities, at fair value (Note 3)	50,808	25,510
Mortgage-Backed Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	1,150	1,648
Available-for-sale securities, at fair value (Note 3)	$ 1,158	$ 1,634

Available-for-sale securities, debt maturities, after three month through one years amortized cost.

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Available-for-sale Securities, debt maturities, after three month through one years fair value.

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Available-for-sale securities, debt maturities three month or less amortized cost.

+ References

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Available-for-sale securities, debt maturities, three month or less fair value.

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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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), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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