Expiration period of each operating loss carryforward.

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- Definition

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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- Definition

Amount of unrecognized tax benefits.

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Income Taxes and Deferred Tax Asset/Liability - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Tax rate change	$ 19,545,000	$ 0	$ 0
AMT credit carryforwards	146,000
Valuation allowance for deferred tax assets	36,545,000	58,034,000
Deferred tax assets, valuation allowance	7,249,000	$ 11,494,000
Accrued income tax penalties and interest	0		$ 0
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 109,500,000
Operating loss carryforward, expiration period	20 years
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 57,700,000
State and Local Jurisdiction \| Minimum
Operating Loss Carryforwards [Line Items]
Operating loss carryforward, expiration period	5 years
State and Local Jurisdiction \| Maximum
Operating Loss Carryforwards [Line Items]
Operating loss carryforward, expiration period	20 years
Will be Recognized as Reduction of Income Tax Expense
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits	$ 30,400,000
Will Be Recorded As Increase in Equity
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits	$ 6,100,000