Income Taxes (Narrative) (Details) - MARYLAND [Member] - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Operating loss carryforwards	$ 40.4
Deferred tax assets, operating loss carryforwards, state and local	2.7
Operating loss carryforward, valuation allowance	$ 2.7	$ 2.6

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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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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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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