Summary of Related Party Costs (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Related party costs, Incurred	$ 6,447,370
Related party costs, Paid	2,123,135
Related party costs, Payable	4,324,235	0
Operating expenses (including organizational costs)
Related Party Transaction [Line Items]
Related party costs, Incurred	862,827
Related party costs, Paid	26,326
Related party costs, Payable	836,501
Asset management fees
Related Party Transaction [Line Items]
Related party costs, Incurred	22,254
Related party costs, Paid	0
Related party costs, Payable	22,254
Property management fees
Related Party Transaction [Line Items]
Related party costs, Incurred	47,287
Related party costs, Paid	0
Related party costs, Payable	47,287
Acquisition expenses
Related Party Transaction [Line Items]
Related party costs, Incurred	1,089,783
Related party costs, Paid	386,750
Related party costs, Payable	703,033
Deferred financing costs
Related Party Transaction [Line Items]
Related party costs, Incurred	441,873
Related party costs, Paid	0
Related party costs, Payable	441,873
Other assets
Related Party Transaction [Line Items]
Related party costs, Incurred	461,492
Related party costs, Paid	0
Related party costs, Payable	461,492
Selling commissions
Related Party Transaction [Line Items]
Related party costs, Incurred	1,201,157
Related party costs, Paid	1,201,157
Related party costs, Payable	0
Dealer Manager fee
Related Party Transaction [Line Items]
Related party costs, Incurred	514,781
Related party costs, Paid	508,902
Related party costs, Payable	5,879
Offering costs
Related Party Transaction [Line Items]
Related party costs, Incurred	1,805,916
Related party costs, Paid	0
Related party costs, Payable	$ 1,805,916