Real Estate (Intangible Assets, Lease Liabilities, and Related Amortization) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Intangible lease liabilities (included in other liabilities):
Below-market in-place leases	$ 41,077		$ 41,101
Less: accumulated amortization	(26,559)		(26,486)
Below-market in-place leases, net	14,518		14,615
Above-market in-place leases
Intangible lease assets (included in other assets):
Leases	15,408		15,474
Less: accumulated amortization	(10,327)		(10,271)
Leases, net	5,081		5,203
In-place leases
Intangible lease assets (included in other assets):
Leases	121,486		118,416
Less: accumulated amortization	(68,986)		(68,695)
Leases, net	52,500		$ 49,721
Intangible lease liabilities (included in other liabilities):
Amortization expense, in-place leases	1,800	$ 2,395
Above-market and below-market in-place leases
Intangible lease liabilities (included in other liabilities):
Amortization expense, above- and below-market leases	$ 162	$ 220

Amount of non-cash amortization of intangible asset (liability) for above and below market leases.

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