Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Loss Carryforwards [Line Items]
NOL carryforwards	$ 67,900,000
Effective income tax rate (as a percent)	47.00%	34.00%	34.00%
Valuation allowance	$ 0	$ 0	$ 0
Unrecognized tax benefits	$ 0	$ 0	$ 0
Observatory \| Operating Segments
Operating Loss Carryforwards [Line Items]
Increase of U.S. corporation income tax benefit as a result of NOL carryback from CARES Act (as a percent)	13.00%
NOL carryforwards	$ 3,800,000
Income tax receivable	$ 8,100,000

Effective Income Tax Rate Reconciliation, Operating Loss Carryback, CARES Act, Percent

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

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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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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Amount of unrecognized tax benefits.

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