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Summary of Significant Accounting Policies - Derivative Financial Instruments (Details)
12 Months Ended
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Feb. 28, 2019
USD ($)
derivative
Derivative [Line Items]        
Loss on interest rate swaps $ 14,917,000 $ 0 $ 0  
Interest Rate Swap Agreements        
Derivative [Line Items]        
Number of derivative agreements | derivative       4
Weighted average fixed interest rate on notional amounts       2.48%
Notional amount       $ 400,000,000.0
Loss on interest rate swaps $ 14,900,000