Cash and cash equivalents maturity period.

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Finite lived intangible assets write off.

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Percentage of ordinary taxable income distributed to stockholders.

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Revenue recognized rent.

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Significant accounting policies.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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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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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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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 cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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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.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Significant Accounting Policies [Line Items]
Federal Deposit Insurance Corporation deposit insurance limit per institution	$ 250,000		$ 250,000
Restricted cash	8,265,000		8,265,000		$ 4,634,000
Bad debt expense	236,000	$ 101,000	286,000	$ 670,000
Amortization expense for intangible assets	567,000	416,000	2,900,000	664,000
Additional amortization expense on current in-place intangible assets	358,000		358,000
Write-off intangible assets	1,641,000	0	4,155,000	0
Depreciation expense	10,216,000	8,255,000	30,690,000	23,625,000
Recognized contract assets	0		0
Recognized contract liabilities	0		0
Advertising expenses	577,000	437,000	1,674,000	1,285,000
Transfers of assets between Level 1 and Level 2	0	0	0	0
Transfers of assets between Level 2 and Level 1	0	0	0	0
Transfers of liabilities between Level 1 and Level 2	0	0	0	0
Transfers of liabilities between Level 2 and Level 1	0	0	0	0
Income tax expense	0	0	$ 0	0
Taxable income distributable to stockholders			90.00%
ASC Topic 230
Significant Accounting Policies [Line Items]
Decrease in net cash used in investing activities due to new accounting standard adoption				1,147,000
Natural Disasters and Other Insurable Events
Significant Accounting Policies [Line Items]
Rent revenue recognized	65,000	$ 11,000	$ 171,000	$ 96,000
Building and Building Improvements
Significant Accounting Policies [Line Items]
Depreciable Lives			40 years
Leases Acquired In Place
Significant Accounting Policies [Line Items]
Acquisition of above-market in-place leases	$ 715,000		$ 2,356,000
Minimum \| Equipment and Fixtures
Significant Accounting Policies [Line Items]
Depreciable Lives			5 years
Maximum
Significant Accounting Policies [Line Items]
Cash And Cash Equivalents Maturity Period			3 months
Maximum \| Equipment and Fixtures
Significant Accounting Policies [Line Items]
Depreciable Lives			10 years