Summary of Significant Accounting Policies - Additional Information (Detail)			12 Months Ended
	Jan. 01, 2021 Segment	Jul. 01, 2018 USD ($) ShoppingCenter shares	Dec. 31, 2020 USD ($) Affiliate Segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 26, 2018
Summary Of Significant Accounting Policies [Line Items]
Mortgage indebtedness			$ 249,260,000	$ 94,874,000
Maximum exposure to losses associated with VIEs				114,000,000.0
Capitalized costs			3,000,000.0	3,800,000	$ 5,700,000
Impairment charges related to consolidated real estate investment			5,200,000	3,370,000	69,324,000
Interest paid			76,000,000.0	79,500,000	148,400,000
Capitalized interest paid			900,000	1,300,000	1,100,000
Reserve of preferred equity interest			19,393,000	15,544,000	11,422,000
Accounts receivable, not probable of being collected amount			4,700,000	1,000,000.0
Allowance for straight line rent			2,100,000	2,800,000
Straight line rent receivable, net			$ 29,300,000	31,200,000
Contract asset, explanation of change			The portion of payments retained by the customer until the second contingent event is not considered a significant financing component because the right to payment is expected to become unconditional within one year or less.  Contract assets are transferred to receivables when the right to payment becomes unconditional
Stock-based compensation cost recognized by the company			$ 8,000,000.0	9,200,000	7,700,000
Accelerated vesting of awards due to employee separation charges					1,400,000
Number of reportable segments | Segment	1		2
Quantitative threshold of revenues, profit or loss and assets for identifying reportable segments			The Company’s chief operating decision maker may review operational and financial data on a property basis and does not differentiate properties on a geographical basis for purposes of allocating resources or capital.  The Company evaluates individual property performance primarily based on net operating income before depreciation, amortization and certain nonrecurring items.  Each consolidated shopping center is considered a separate operating segment; however, each shopping center, on a stand-alone basis, represents less than 10% of revenues, profit or loss, and assets of the combined reported operating segment and meets the majority of the aggregations criteria under the applicable standard.
Adoption of Topic 606 [Member]
Summary Of Significant Accounting Policies [Line Items]
Revenue recognized percentage upon lease execution			50.00%
Revenue recognized percentage upon tenant rent commencement			50.00%
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating lease term			30 years
Maximum [Member] | Geographic Concentration Risk [Member] | Revenues [Member] | Shopping Center [Member] | Stand-Alone Shopping Center [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of revenues			10.00%
Maximum [Member] | Tenant [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating lease term			30 years
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating lease term			1 month
Minimum [Member] | Tenant [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating lease term			1 month
Real Estate Investment [Member]
Summary Of Significant Accounting Policies [Line Items]
Impairment charges related to consolidated real estate investment			$ 5,200,000	3,400,000	$ 69,300,000
Mortgages [Member]
Summary Of Significant Accounting Policies [Line Items]
Mortgage indebtedness			$ 249,300,000	$ 94,900,000
Retail Value Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
Disposition fees equal to percentage of gross sale price			1.00%
Retail Value Inc. [Member] | Series A Preferred Stock [Member] | Aggregate Gross Proceeds of RVI's Asset Sales Subsequent to July 1, 2018 Exceeds $2.0 Billion [Member]
Summary Of Significant Accounting Policies [Line Items]
Preferred stock, value		$ 190,000,000
Maximum increase in preferred stock amount		$ 10,000,000
Variable Interest Entity, Not Primary Beneficiary [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of unconsolidated joint ventures | Affiliate			2
Spin-off [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Dividend payments to be received will be recorded as reduction of preferred shares carrying value			$ 190,000,000
Spin-off [Member] | Retail Value Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of shopping centers in connection with spinoff | ShoppingCenter		48
Gross asset value		$ 2,700,000,000
Percentage of distribution of outstanding common shares rights to holders						100.00%
Spin off distribution description		On the spin-off date, holders of SITE Centers’ common shares received one common share of RVI for every ten shares of SITE Centers’ common stock held on the record date.
Spin-off [Member] | Retail Value Inc. [Member] | Series A Preferred Stock [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of shares retained | shares		1,000
Spin-off [Member] | Retail Value Inc. [Member] | Series A Preferred Stock [Member] | Aggregate Gross Proceeds of RVI's Asset Sales Subsequent to July 1, 2018 Exceeds $2.0 Billion [Member]
Summary Of Significant Accounting Policies [Line Items]
Preferred stock, value		$ 190,000,000
Maximum increase in preferred stock amount		10,000,000
Spin-off [Member] | Retail Value Inc. [Member] | Mortgages [Member]
Summary Of Significant Accounting Policies [Line Items]
Mortgage indebtedness		$ 1,270,000,000
U.S. [Member] | Spin-off [Member] | Retail Value Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of shopping centers in connection with spinoff | ShoppingCenter		36
Puerto Rico [Member] | Spin-off [Member] | Retail Value Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of shopping centers in connection with spinoff | ShoppingCenter		12