Risk Management and Derivatives (Derivative Instrument Gain (Loss)) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Income $ 271  
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Earnings 32,518  
Designated as Hedging Instrument | Interest Expense | Interest rate swap    
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Income (32,518) $ (6,745)
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Earnings (271) 252
Not Designated as Hedging Instrument | Interest Expense | Interest rate cap    
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Income $ (4) $ (13)