Income Taxes Income Taxes (Details 4) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation allowance at beginning of year	$ 15,250
Change in accounting for stock compensation windfalls	1,112
Current year operating loss	3,048
Change in tax rate to 21%	(7,504)
Other	(1,403)
Valuation allowance at end of year	$ 13,309

Valuation Allowance, Deferred Tax, Increase (Decrease), Current Year Operating Loss, Amount

No definition available.

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- Definition

Valuation Allowance, Deferred Tax, Increase (Decrease), Effective Tax Rate Change, Amount

+ References

No definition available.

+ Details

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- Definition

Valuation Allowance, Deferred Tax, Increase (Decrease), Other, Amount

+ References

No definition available.

+ Details

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- Definition

Valuation Allowance, Deferred Tax, Increase (Decrease), Stock Compensation Expense, Amount

+ References

No definition available.

+ Details

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

+ Details

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- Definition

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.

+ Details

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