Percentage of current base rent.

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- Definition

Amount of purchase option price for real estate for Land and buildings.

+ References

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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- Definition

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

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No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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Summary of Significant Accounting Policies and Procedures and Recent Accounting Pronouncements - Additional Information (Details)			9 Months Ended
	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2020 USD ($) segment	Sep. 30, 2019 USD ($)
Number of Reportable Segments \| segment			1
Impairment loss			$ 0	$ 0
Short-term Investments	$ 451,178,000	$ 119,595,000	$ 451,178,000
Percentage of current base rent	8.00%		8.00%
Purchase Option Price For Real Estate For Land And Buildings	$ 30,500,000		$ 30,500,000
Cash, FDIC Insured Amount	250,000		250,000
Money Market Funds [Member]
Short-term Investments	$ 93,500,000	$ 60,100,000	$ 93,500,000
Building [Member]
Property, Plant and Equipment, Useful Life			40 years
Florida, Illinois, Michigan, and Pennsylvania Property [Member]
Concentration Risk, Percentage	5.00%
New York Property [Member]
Concentration Risk, Percentage		6.00%
Minimum [Member] \| Office Equipment And Furniture And Fixtures [Member]
Property, Plant and Equipment, Useful Life			3 years
Maximum [Member] \| Office Equipment And Furniture And Fixtures [Member]
Property, Plant and Equipment, Useful Life			6 years