Business Segments - Schedule of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Real estate rental operations:
Revenue	$ 58,141		$ 56,081		$ 117,891	$ 112,190
Income from real estate	44,207		42,571		88,808	84,712
Interest expense, net and amortization of deferred debt costs	(10,793)		(11,168)		(21,860)	(22,594)
Depreciation and amortization of deferred leasing costs	(11,524)		(11,351)		(23,167)	(22,700)
General and administrative	(5,140)		(4,647)		(9,954)	(9,068)
Change in fair value of derivatives	0		(12)		0	(12)
Gain on sale of property	0		509		0	509
Net Income	16,750	$ 17,077	15,902	$ 14,947	33,827	30,847
Capital investment	45,176		20,270		68,599	36,993
Total assets	1,569,162		1,446,482		1,569,162	1,446,482	$ 1,527,489
Operating Segments | Shopping Centers
Real estate rental operations:
Revenue	42,259		40,755		85,417	81,679
Income from real estate	33,707		32,274		67,177	64,322
Interest expense, net and amortization of deferred debt costs	0		0		0	0
Depreciation and amortization of deferred leasing costs	(7,375)		(7,333)		(14,657)	(14,631)
General and administrative	0		0		0	0
Change in fair value of derivatives			0			0
Gain on sale of property			509			509
Net Income	26,332		25,450		52,520	50,200
Capital investment	8,967		3,883		13,580	7,143
Total assets	970,028		804,939		970,028	804,939
Operating Segments | Mixed-Use Properties
Real estate rental operations:
Revenue	15,882		15,326		32,474	30,511
Income from real estate	10,500		10,297		21,631	20,390
Interest expense, net and amortization of deferred debt costs	0		0		0	0
Depreciation and amortization of deferred leasing costs	(4,149)		(4,018)		(8,510)	(8,069)
General and administrative	0		0		0	0
Change in fair value of derivatives			0			0
Gain on sale of property			0			0
Net Income	6,351		6,279		13,121	12,321
Capital investment	36,209		16,387		55,019	29,850
Total assets	590,294		464,534		590,294	464,534
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	(10,793)		(11,168)		(21,860)	(22,594)
Depreciation and amortization of deferred leasing costs	0		0		0	0
General and administrative	(5,140)		(4,647)		(9,954)	(9,068)
Change in fair value of derivatives			(12)			(12)
Gain on sale of property			0			0
Net Income	(15,933)		(15,827)		(31,814)	(31,674)
Capital investment	0		0		0	0
Total assets	8,840		177,009		8,840	177,009
Real Estate
Real estate rental operations:
Expenses	(13,934)		(13,510)		(29,083)	(27,478)
Real Estate | Operating Segments | Shopping Centers
Real estate rental operations:
Expenses	(8,552)		(8,481)		(18,240)	(17,357)
Real Estate | Operating Segments | Mixed-Use Properties
Real estate rental operations:
Expenses	(5,382)		(5,029)		(10,843)	(10,121)
Real Estate | Corporate and Other
Real estate rental operations:
Expenses	$ 0		$ 0		$ 0	$ 0