Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) Property State	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) Property Segment State	Dec. 31, 2015 USD ($)	Jul. 07, 2015 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of reportable segments | Segment			1
Impairment loss on real estate assets	$ 0		$ 0
Impairment loss	0		0
Restricted cash	81,790,000		81,790,000	$ 92,475,000
Prepaid rental income	$ 14,600,000		$ 14,600,000
Number of wholly owned properties acquired | Property	235		235
Number of states in properties located | State	49		49
Interest Rate Cap [Member]
Summary Of Significant Accounting Policies [Line Items]
Interest rate caps purchased	$ 5,000,000		$ 5,000,000
Derivative, term of contract			4 years
Notional amount	1,260,000,000		$ 1,260,000,000
Derivative strike rate			3.50%
Derivative losses	$ 47,000	$ 2,800,000	$ 1,900,000
Master Lease [Member]
Summary Of Significant Accounting Policies [Line Items]
Right to recapture property space	50.00%		50.00%
Sears Holdings Corporation [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted cash					$ 22,609,000
Right to recapture property space	100.00%		100.00%
Sears Holdings Corporation [Member] | Master Lease [Member]
Summary Of Significant Accounting Policies [Line Items]
Right to recapture property space	100.00%		100.00%
Future Capital Investments [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	$ 35,800,000		$ 35,800,000
Basic Property Carrying Costs [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	$ 31,400,000		$ 31,400,000
Operating Partnership [Member] | ESL [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of operating partnership interest held by parent	56.70%		56.70%