Marketable Securities - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Fair market value of investment securities exceeds cost basis	$ 109		$ 109
Gross unrealized holding gains	110		110
Gross unrealized holding losses	1		1
Unrealized gain (loss) on available-for-sale securities	(11)	$ 182	58	$ 384
Estimated tax expense (benefit) of change in value of available-for-sale securities			16
Accrued interest receivable balance	$ 125		$ 125

Debt Securities, Available for sale securities, fair market value exceeds cost basis, by amount.

No definition available.

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- Definition

Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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- Definition

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).

+ References

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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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Amount, after tax and before adjustment, of unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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