Short-term Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Table summarizes the amortized cost and estimated fair value of the Company’s marketable securities
Amortized Cost	$ 54,223	$ 35,739
Unrealized Gains	53
Unrealized Losses		(7)
Fair Value	54,276	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	11,872	6,059
Unrealized Gains	10
Fair Value	11,882	6,059
U.S. Treasury securities
Table summarizes the amortized cost and estimated fair value of the Company’s marketable securities
Amortized Cost	42,351	29,680
Unrealized Gains	43
Unrealized Losses		(7)
Fair Value	$ 42,394	$ 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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-Section 50
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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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-Section 50
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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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