Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Leased Assets [Line Items]
Operating Lease, Weighted Average Discount Rate, Percent	5.80%
Operating Lease, Weighted Average Remaining Lease Term	51 years
Operating Leases, Future Minimum Payments Receivable [Abstract]
Operating Leases, Future Minimum Payments Receivable, Current	$ 449,665
Operating Leases, Future Minimum Payments Receivable, in Two Years	407,615
Operating Leases, Future Minimum Payments Receivable, in Three Years	361,062
Operating Leases, Future Minimum Payments Receivable, in Four Years	328,486
Operating Leases, Future Minimum Payments Receivable, in Five Years	301,404
Operating Leases, Future Minimum Payments Receivable, Thereafter	$ 742,806
Number of centers with option to extend lease term for three 10-year periods	One
Number of 10-year periods that one center has the option to extend	three
Number of centers with option to extend lease term for one 10-year period	one
Lessee, Operating Lease, Renewal Term	10 years
Number of Lease Extension Options	one
Operating Leases, Rent Expense	$ 16,200	$ 17,200	$ 16,300
Operating Leases, Rent Expense, Contingent Rentals	400	300	$ 0
Payables representing straightline rent adjustments under lease agreements		$ 64,800
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	14,357
Operating Leases, Future Minimum Payments, Due in Two Years	12,586
Operating Leases, Future Minimum Payments, Due in Three Years	13,982
Operating Leases, Future Minimum Payments, Due in Four Years	14,142
Operating Leases, Future Minimum Payments, Due in Five Years	14,144
Operating Leases, Future Minimum Payments, Due Thereafter	$ 708,924
City Creek Center [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Company's ownership in leasehold interest	100.00%
Accounting Standards Update 2016-02 [Member]
Operating Leased Assets [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	$ 4,400