Right-of-Use Assets and Operating Lease Liabilities (Lease Information) (Details) $ in Thousands	Dec. 31, 2019 USD ($) lease
Lessee, Lease, Description [Line Items]
Number of ground leases | lease	3
Ground Leases
Lessee, Lease, Description [Line Items]
Operating lease – ROU assets	$ 4,481
Operating lease – lease liabilities	$ (6,175)
Weighted average remaining lease term	14 years 3 months 18 days
Weighted average discount rate	4.10%
Operating lease - accrued lease payments	$ 1,694
Headquarters Office Lease
Lessee, Lease, Description [Line Items]
Operating lease – ROU assets	2,991
Operating lease – lease liabilities	$ (3,629)
Weighted average remaining lease term	5 years 3 months 18 days
Weighted average discount rate	3.50%
Operating lease - accrued lease payments	$ 638