Marketable Securities - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Fair market value of investment securities exceeds cost basis	$ (187)
Gross unrealized holding gains	3
Gross unrealized holding losses	190
Unrealized gain (loss) on available-for-sale securities	202	$ (302)
Estimated tax expense (benefit) of change in value of available-for-sale securities	$ (42)

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

No definition available.

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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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-Section 50
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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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- Definition

Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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- Definition

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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