Short-term Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Table summarizes the amortized cost and estimated fair value of the Company’s marketable securities
Amortized Cost	$ 33,487	$ 35,739
Unrealized Gains	22
Unrealized Losses		(7)
Fair Value	33,509	35,732
U.S. government-sponsored enterprise securities
Table summarizes the amortized cost and estimated fair value of the Company’s marketable securities
Amortized Cost	6,091	6,059
Unrealized Gains	3
Fair Value	6,094	6,059
U.S. Treasury securities
Table summarizes the amortized cost and estimated fair value of the Company’s marketable securities
Amortized Cost	27,396	29,680
Unrealized Gains	19
Unrealized Losses		(7)
Fair Value	$ 27,415	$ 29,673

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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-Topic 320
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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).

+ References

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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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
-Topic 320
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