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Derivative and Other Fair Value Instruments - Additional Information (Details)
 1 Months Ended 12 Months Ended
Jul. 31, 2019
USD ($)
DerivativeInstrument
Jun. 30, 2019
USD ($)
DerivativeInstrument
Nov. 30, 2018
USD ($)
DerivativeInstrument
Feb. 28, 2018
USD ($)
DerivativeInstrument
Aug. 31, 2017
USD ($)
DerivativeInstrument
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Derivative [Line Items]                
Unrealized gain (loss) on interest rate cash flow hedges, pretax, accumulated other comprehensive income (loss)           $ 77,600,000 $ 65,000,000.0  
Interest rate cash flow hedge gain (loss) to be reclassified during next 12 months, net           24,900,000    
Number of interest rate swaps matured | DerivativeInstrument 6              
Repayments of unsecured debt           $ 1,050,000,000   $ 497,975,000
Forward Starting Swaps [Member]                
Derivative [Line Items]                
Proceeds from settlement of derivative instruments   $ 41,800,000 $ 16,400,000 $ 1,600,000 $ 1,300,000      
Forward starting swaps settled | DerivativeInstrument   10 6 2 4      
Interest expense   $ 200,000 $ 120,000          
Increase (decrease) in charges hedge termination activities   41,600,000 (16,500,000) $ (1,600,000) $ (1,300,000)      
Total commitment amount   $ 600,000,000.0 $ 400,000,000.0 $ 500,000,000.0 $ 400,000,000.0      
Debt instrument, term   10 years 10 years 10 years 10 years      
2.375% Notes [Member]                
Derivative [Line Items]                
Repayments of unsecured debt $ 450,000,000.0              
Debt instrument, interest rate, stated percentage 2.375%