Income Tax - Additional Information (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 991,000	$ 231,000	$ 2,374,000	$ 637,000
Effective tax rate	(0.15%)	(0.13%)	(0.13%)	(0.15%)
Interest and penalties recognized			$ 0
Unrecognized tax benefits	$ 0		$ 0		$ 0

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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Amount of unrecognized tax benefits.

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