Business Segments - Schedule of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Real estate rental operations:
Revenue	$ 56,760			$ 57,052			$ 166,923	$ 174,943
Income from real estate	41,821			42,413			124,034	131,221
Interest expense, net and amortization of deferred debt costs	(12,398)			(10,325)			(34,011)	(32,185)
Depreciation and amortization of deferred leasing costs	(13,713)			(12,018)			(37,593)	(35,185)
General and administrative	(4,107)			(4,742)			(13,790)	(14,696)
Net Income	11,603	$ 10,208	$ 16,829	15,328	$ 16,750	$ 17,077	38,640	49,155
Capital investment	9,436			36,456			48,363	105,055
Total assets	1,681,374			1,646,764			1,681,374	1,646,764	$ 1,618,340
Operating Segments | Shopping Centers
Real estate rental operations:
Revenue	40,336			41,313			120,236	126,730
Income from real estate	31,581			32,339			94,195	99,516
Interest expense, net and amortization of deferred debt costs	0			0			0	0
Depreciation and amortization of deferred leasing costs	(8,169)			(7,260)			(22,812)	(21,917)
General and administrative	0			0			0	0
Net Income	23,412			25,079			71,383	77,599
Capital investment	2,733			9,166			11,622	22,746
Total assets	982,381			985,244			982,381	985,244
Operating Segments | Mixed-Use Properties
Real estate rental operations:
Revenue	16,424			15,739			46,687	48,213
Income from real estate	10,240			10,074			29,839	31,705
Interest expense, net and amortization of deferred debt costs	0			0			0	0
Depreciation and amortization of deferred leasing costs	(5,544)			(4,758)			(14,781)	(13,268)
General and administrative	0			0			0	0
Net Income	4,696			5,316			15,058	18,437
Capital investment	6,703			27,290			36,741	82,309
Total assets	643,395			609,560			643,395	609,560
Corporate and Other
Real estate rental operations:
Revenue	0			0			0	0
Income from real estate	0			0			0	0
Interest expense, net and amortization of deferred debt costs	(12,398)			(10,325)			(34,011)	(32,185)
Depreciation and amortization of deferred leasing costs	0			0			0	0
General and administrative	(4,107)			(4,742)			(13,790)	(14,696)
Net Income	(16,505)			(15,067)			(47,801)	(46,881)
Capital investment	0			0			0	0
Total assets	55,598			51,960			55,598	51,960
Real Estate
Real estate rental operations:
Expenses	(14,939)			(14,639)			(42,889)	(43,722)
Real Estate | Operating Segments | Shopping Centers
Real estate rental operations:
Expenses	(8,755)			(8,974)			(26,041)	(27,214)
Real Estate | Operating Segments | Mixed-Use Properties
Real estate rental operations:
Expenses	(6,184)			(5,665)			(16,848)	(16,508)
Real Estate | Corporate and Other
Real estate rental operations:
Expenses	$ 0			$ 0			$ 0	$ 0