Commitments And Contingencies (Ground Lease Agreements) (Narrative) (Details) |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
|
Jun. 30, 2019
USD ($)
|
Jun. 30, 2018
USD ($)
|
Jun. 30, 2019
USD ($)
item
|
Jun. 30, 2018
USD ($)
|
|
| Lessee, Lease, Description [Line Items] | ||||
| Ground lease expense incurred | $ 640,000 | $ 550,000 | $ 1,300,000 | $ 1,100,000 |
| Operating lease | $ 23,735,000 | $ 23,735,000 | ||
| Number of ground leases | item | 5 | |||
| Minimum [Member] | ||||
| Lessee, Lease, Description [Line Items] | ||||
| Term of lease contract | 6 years 3 months | 6 years 3 months | ||
| Borrowing rate | 5.637% | 5.637% | ||
| Maximum [Member] | ||||
| Lessee, Lease, Description [Line Items] | ||||
| Term of lease contract | 82 years 6 months 29 days | 82 years 6 months 29 days | ||
| Borrowing rate | 7.618% | 7.618% | ||
| Accounting Standards Update 2016-02 [Member] | ||||
| Lessee, Lease, Description [Line Items] | ||||
| Operating lease | $ 22,500,000 | $ 22,500,000 | ||