Income Taxes - Unrecognized tax benefits (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Unrecognized tax benefits
Unrecognized tax benefits	$ 0	$ 11
U.S Federal
Income Taxes
Net operating loss carryforward	3,000,000
State
Income Taxes
Net operating loss carryforward	$ 2,300,000

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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