Investments in and Advances to Joint Ventures - Condensed Combined Financial Information of Company's Unconsolidated Joint Venture Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Condensed Combined Balance Sheets
Land	$ 953,556	$ 881,397
Buildings	3,488,499	3,277,440
Fixtures and tenant improvements	509,866	491,312
Total real estate rental property	4,951,921	4,650,149
Less: Accumulated depreciation	(1,427,057)	(1,289,148)
Real estate rental property, net	3,524,864	3,361,001
Construction in progress and land	37,467	59,663
Total real estate assets, net	3,562,331	3,420,664
Other assets, net	130,690	108,631
Total assets	4,108,284	4,093,622
Mortgage debt	249,260	94,874
Total liabilities	2,163,461	2,112,144
Accumulated equity	1,944,823	1,981,478	$ 2,073,002	$ 2,897,438
Total liabilities and equity	4,108,284	4,093,622
Company's share of accumulated equity	72,555	186,247
Redeemable preferred equity, net	0	112,589
Basis differentials	1,644	(6,864)
Deferred development fees, net of portion related to the Company's interest	(1,277)	(2,452)
Amounts payable to the Company	4,375	4,975
Investments in and Advances to Joint Ventures, net	77,297	294,495
Unconsolidated Joint Ventures [Member]
Condensed Combined Balance Sheets
Land	441,412	895,427
Buildings	1,258,879	2,583,053
Fixtures and tenant improvements	137,663	233,303
Total real estate rental property	1,837,954	3,711,783
Less: Accumulated depreciation	(492,288)	(949,879)
Real estate rental property, net	1,345,666	2,761,904
Construction in progress and land	58,201	58,855
Total real estate assets, net	1,403,867	2,820,759
Cash and restricted cash	35,212	109,260
Receivables, net	25,719	37,191
Other assets, net	61,381	147,129
Total assets	1,526,179	3,114,339
Mortgage debt	1,029,579	1,640,146
Notes and accrued interest payable to the Company	4,375	4,975
Other liabilities	57,349	142,754
Total liabilities	1,091,303	1,787,875
Redeemable preferred equity – SITE Centers	0	217,871
Accumulated equity	434,876	1,108,593
Total liabilities and equity	$ 1,526,179	$ 3,114,339