Quarterly report pursuant to Section 13 or 15(d)

Long-term Debt - Additional Information (Details)

v3.20.2
Long-term Debt - Additional Information (Details)
3 Months Ended 6 Months Ended
Jul. 15, 2021
Jun. 05, 2020
$ / shares
Feb. 20, 2020
$ / shares
Dec. 13, 2019
$ / shares
Sep. 12, 2019
$ / shares
Jun. 06, 2019
$ / shares
Feb. 21, 2019
$ / shares
Jun. 30, 2020
USD ($)
$ / shares
Jun. 30, 2019
USD ($)
Jun. 30, 2020
USD ($)
$ / shares
Jun. 30, 2019
USD ($)
Dec. 31, 2019
USD ($)
Sep. 30, 2019
USD ($)
Debt Instrument [Line Items]                          
Maximum unencumbered assets percentage of unsecured debt               120.00%   120.00%      
Principal, net of issuance costs               $ 626,000,000   $ 626,000,000   $ 700,000,000  
Total interest expense               21,664,000 $ 14,869,000 $ 39,798,000 $ 30,300,000    
Amount per share, declared (in usd per share) | $ / shares   $ 0.340 $ 0.340 $ 0.335 $ 0.335 $ 0.335 $ 0.335     $ 0.34      
Senior Unsecured Notes                          
Debt Instrument [Line Items]                          
Principal               900,000,000   $ 900,000,000   500,000,000  
Proceeds from issuance of debt                   157,000,000      
Senior Unsecured Notes | 2024 Notes                          
Debt Instrument [Line Items]                          
Principal               $ 500,000,000   $ 500,000,000     $ 150,000,000
Interest rate               5.25%   5.25%      
Principal, net of issuance costs               $ 155,000,000   $ 155,000,000      
Yield to maturity                   4.13%      
Total interest expense               12,000,000   $ 18,000,000      
Senior Unsecured Notes | 2024 Notes | Forecast                          
Debt Instrument [Line Items]                          
Redemption price, percentage 40.00%                        
Offer share percentage 105.25%                        
Convertible Senior Notes | Senior Unsecured Notes Due 2025                          
Debt Instrument [Line Items]                          
Principal               $ 400,000,000   $ 400,000,000      
Interest rate               6.00%   6.00%      
Convertible Senior Notes | 4.125% Convertible Senior Notes Due September 1, 2022                          
Debt Instrument [Line Items]                          
Principal               $ 150,000,000   $ 150,000,000   $ 150,000,000  
Interest rate               4.125%   4.125%      
Redemption price, percentage                   100.00%      
Principal, net of issuance costs               $ 145,000,000   $ 145,000,000      
Total interest expense               $ 2,000,000 $ 2,000,000 $ 4,000,000 $ 4,000,000    
Conversion rate of shares for each $1,000 principal amount of convertible notes                   0.036768      
Conversion price per share (in usd per share) | $ / shares               $ 27.20   $ 27.20      
Adjustment for dividends declared (in usd per share) | $ / shares                   $ 0.33