Expiration period of each operating loss carryforward.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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

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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.

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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.

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

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Amount of unrecognized tax benefits.

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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			24 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018
Operating Loss Carryforwards [Line Items]
Tax rate change	$ (281,000)	$ 19,545,000	$ 0	$ 19,300,000
AMT credit carryforwards	210,000			210,000
Valuation allowance for deferred tax assets	31,718,000	36,545,000		31,718,000
Deferred taxes	1,450,000	0		1,450,000
Accrued income tax penalties and interest	0	$ 0	$ 0	0
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 94,000,000			94,000,000
Operating loss carryforward, expiration period	18 years
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 52,000,000			52,000,000
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	$ 25,600,000			25,600,000
Will Be Recorded As Increase in Equity
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits	$ 6,100,000			$ 6,100,000