Defined Contribution Plan (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan
Contributions to the 401(k) Plan	$ 137	$ 131
Layering first
Defined Contribution Plan
Eligible Employees to contribute (as a percent)	3.00%
Companys match (as a percent)	100.00%
Layering second
Defined Contribution Plan
Eligible Employees to contribute (as a percent)	2.00%
Companys match (as a percent)	50.00%

The amount of the cost recognized during the period for defined contribution plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

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

No definition available.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

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