Commitments and Contingencies - Additional Information (Details)	3 Months Ended	9 Months Ended
	Jun. 30, 2019 ft²	Sep. 30, 2019 USD ($)	Dec. 31, 2016 USD ($)
Commitments And Contingencies [Line Items]
Lease expiration date		Jan. 03, 2020
Operating leases, future minimum payments, due in 2019		$ 15,288
Millbrook, NY
Commitments And Contingencies [Line Items]
Gross square feet of traditional drive-up storage units and all-climate-controlled units | ft²	16,500
Minimum | Millbrook, NY
Commitments And Contingencies [Line Items]
Construction completion period		9 months
Maximum | Millbrook, NY
Commitments And Contingencies [Line Items]
Construction completion period		12 months
Tuxis
Commitments And Contingencies [Line Items]
Additional cash payment			$ 900,000