Leases - Additional Information (Detail) $ in Thousands				3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) ft² Property	Jul. 06, 2015 Lease Option	Jun. 11, 2015 Property	Sep. 30, 2018 USD ($) ft² Property	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) ft² Property	Sep. 30, 2017 USD ($)	Dec. 31, 2018 Store	Nov. 30, 2018 Store	Oct. 31, 2018 Store	Jul. 07, 2015
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Base rent paid by Sears Holdings and subsidiaries under master lease				$ 50	$ 50	$ 150	$ 150
Number of real estate properties acquisition exercised | Property						70
Gross leasable area | ft²	11,728,387			11,728,387		11,728,387
Number of terminated properties commenced or completed for redevelopment | Property						38
Number of terminated properties sold | Property				5		10
Net proceeds from sale of real estate						$ 170,692	50,887
Gain on sale of real estate						$ 93,419	13,018
Sears Holdings Corporation [Member]
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Right to recapture property space	100.00%			100.00%		100.00%
Number of real estate properties wholly-owned | Property			234
Net proceeds from sale of real estate				$ 15,200		$ 42,300
Gain on sale of real estate				6,500		11,400
Master Lease [Member]
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Lease term		10 years
Number of options for renewal of lease | Option		3
Renewal period of leases		5 years
Final option renewal period		4 years
Base rent paid by Sears Holdings and subsidiaries under master lease						$ 82,700	108,500
Number of real estate properties acquisition exercised | Property						43
Right to recapture property space exercised						100.00%
Number of real estate properties wholly-owned | Property						50
Number of renewal term that will be increased | Lease		2
Percentage of increase annual lease rent											2.00%
Straight-line rental income				$ (2,200)	$ (1,700)	$ (2,600)	$ 100
Right to recapture property space	50.00%			50.00%		50.00%
Number of real estate properties wholly-owned | Property						224
Lease termination, description						While the Company is permitted to exercise its recapture rights all at once or in stages as to any particular property, it is not permitted to recapture all or substantially all of the space subject to the recapture right at more than 50 properties under Master Lease during any lease year.
Master Lease [Member] | Sears Holdings Corporation [Member]
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Number of options for renewal of lease | Option		1
Base rent paid by Sears Holdings and subsidiaries under master lease						$ 48,800
Number of real estate properties acquisition exercised | Property						16
Right to recapture property space exercised						100.00%
Number of real estate properties wholly-owned | Property						4
Right to recapture property space	100.00%			100.00%		100.00%
Number of real estate properties wholly-owned | Property						21
Lease termination, description						The lease termination payment is calculated as the greater of an amount specified at the time the Company entered into the Master Lease with Sears Holdings and an amount equal to 10 times the adjusted EBITDA attributable to such space within the Sears Holdings main store which is not attributable to the space subject to the separate 50% recapture right discussed above for the 12-month period ending at the end of the fiscal quarter ending immediately prior to recapturing such space.
Lease termination fees incurred						$ 57,100
Additional termination fees incurred						$ 61,100
Lease termination notice period						90 days
Percentage of reduction of fixed rent under master lease						20.00%
Master Lease [Member] | Sears Holdings Corporation [Member] | Lease Terminations [Member]
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Base rent paid by Sears Holdings and subsidiaries under master lease	$ 29,400
Number of unprofitable stores terminated | Property	65			65		65
Gross leasable area terminated | ft²	8,900,000			8,900,000		8,900,000
Lease termination fees paid	$ 56,600
Number of terminated properties announced for redevelopment | Property	87			87		87
Master Lease [Member] | Sears Holdings Corporation [Member] | Notice of Intent Terminate Lease Provided [Member]
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Base rent paid by Sears Holdings and subsidiaries under master lease	$ 11,300
Lease termination fees paid	$ 20,700
Number of unprofitable stores to terminate | Property	22			22		22
Gross leasable area | ft²	2,800,000			2,800,000		2,800,000
Total annual base rent, percentage	5.00%			5.00%		5.00%
Master Lease [Member] | Sears Holdings Corporation [Member] | Notice of Intent Terminate Lease Provided [Member] | Subsequent Event [Member]
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Number of stores, rent to be paid | Store										2
Master Lease [Member] | Sears Holdings Corporation [Member] | Notice of Intent Terminate Lease Provided [Member] | Scenario, Forecast [Member]
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Number of stores, rent to be paid | Store								13	7