Income Taxes - Summary of Effective Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
U.S. federal income taxes at the statutory rate	$ 1,945	$ (1,264)
State taxes, net of federal effects	146	(108)
Permanent differences	(244)	10
Impact of state tax rate change to deferred	0	(36)
Other, including effect of Tax Cuts and Jobs Act	1,725	(28)
Change in valuation allowance	(3,802)	1,347
Income tax (benefit) expense	$ (230)	$ (79)

Income Tax Reconciliation, Impact of State Rate Change to Deferred

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Income Tax Reconciliation, Permanent Differences

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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 valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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