Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

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The cash outflow from the acquisition of residential property intended to generate income for the owner.

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Cash received for the sale of real estate that is not part of an investing activity during the current period.

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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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No definition available.

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Recent Real Estate Transactions (Disposals of Properties) (Detail)				9 Months Ended
	Apr. 07, 2017 USD ($)	Mar. 31, 2017 USD ($)	Feb. 27, 2017 USD ($)	Sep. 30, 2017 USD ($) Property	Dec. 31, 2016 USD ($) Property	Dec. 31, 2015 USD ($)
Real Estate Properties [Line Items]
Mortgage notes issued for property acquired				$ 162,919,083	$ 158,886,111	$ 142,638,401
Rangewood Medical Office Building [Member]
Real Estate Properties [Line Items]
Proceeds from sale of property			$ 2,200,000
Sixty Five Dubos Model Homes [Member]
Real Estate Properties [Line Items]
Number of properties \| Property					65
Residential Properties [Member]
Real Estate Properties [Line Items]
Number of properties \| Property				139
Residential Properties [Member] \| Rangewood Medical Office Building [Member]
Real Estate Properties [Line Items]
Proceeds from sale of property			2,200,000
Gain (loss) on sale of property			$ (170,000)
Residential Properties [Member] \| Regatta Square Retail Center [Member]
Real Estate Properties [Line Items]
Proceeds from sale of property		$ 3,000,000
Gain (loss) on sale of property		$ 756,000
Residential Properties [Member] \| Shoreline Medical Building [Member]
Real Estate Properties [Line Items]
Proceeds from sale of property	$ 8,200,000
Gain (loss) on sale of property	$ 1,300,000
Residential Properties [Member] \| Fourteen Dubose Model Homes [Member]
Real Estate Properties [Line Items]
Proceeds from sale of property				$ 5,300,000
Gain (loss) on sale of property				$ 350,000
Number of properties \| Property				14
Residential Properties [Member] \| Forty-Five Dubose Model Homes [Member]
Real Estate Properties [Line Items]
Number of properties \| Property				45
Purchase price of property acquired				$ 16,800,000
Cash payment for the properties acquired				5,700,000
Mortgage notes issued for property acquired				$ 11,100,000
Residential Properties [Member] \| Sixty Five Dubos Model Homes [Member]
Real Estate Properties [Line Items]
Purchase price of property acquired					$ 23,667,535