Quarterly report pursuant to Section 13 or 15(d)

Long-term Debt - Additional Information (Details)

v3.19.3
Long-term Debt - Additional Information (Details)
3 Months Ended 9 Months Ended
Jul. 15, 2021
Apr. 04, 2019
$ / shares
Sep. 30, 2019
USD ($)
$ / shares
Jun. 30, 2019
$ / shares
Mar. 31, 2019
$ / shares
Dec. 31, 2018
USD ($)
$ / shares
Sep. 30, 2018
USD ($)
$ / shares
Jun. 30, 2018
$ / shares
Mar. 31, 2018
$ / shares
Sep. 30, 2019
USD ($)
$ / shares
Sep. 30, 2018
USD ($)
Jul. 31, 2019
USD ($)
Debt Instrument [Line Items]                        
Principal, net of issuance costs     $ 665,000,000     $ 835,000,000       $ 665,000,000    
Total interest expense     $ 16,561,000       $ 19,681,000     46,861,000 $ 57,424,000  
Dividends declared per share (in usd per share) | $ / shares     $ 0.335 $ 0.335 $ 0.335 $ 0.330 $ 0.330 $ 0.330 $ 0.330      
Senior Unsecured Notes [Member]                        
Debt Instrument [Line Items]                        
Principal     $ 150,000,000             150,000,000    
Principal, net of issuance costs                       $ 344,000,000
Proceeds from issuance of debt                   157,000,000    
Senior Unsecured Notes [Member] | 2024 Notes [Member]                        
Debt Instrument [Line Items]                        
Principal     500,000,000             500,000,000   $ 350,000,000
Principal, net of issuance costs     155,000,000             155,000,000    
Interest rate                       5.25%
Maximum unencumbered assets percentage of unsecured debt                       120.00%
Total interest expense     5,000,000                  
Senior Unsecured Notes [Member] | 2024 Notes [Member] | Forecast [Member]                        
Debt Instrument [Line Items]                        
Redemption price, percentage 40.00%                      
Offer share percentage 105.25%                      
Convertible Senior Notes [Member] | 4.125% Convertible Senior Notes Due September 1, 2022 [Member]                        
Debt Instrument [Line Items]                        
Principal     150,000,000     $ 150,000,000       150,000,000    
Principal, net of issuance costs     $ 145,000,000             $ 145,000,000    
Interest rate     4.125%             4.125%    
Redemption price, percentage                   100.00%    
Total interest expense     $ 2,000,000       $ 2,000,000     $ 5,000,000 $ 5,000,000  
Conversion rate of shares for each $1,000 principal amount of convertible notes   36.7179                    
Conversion price per share (in usd per share) | $ / shares   $ 27.23                    
Adjustment for dividends declared (in usd per share) | $ / shares                   $ 0.335