XML 18 R40.htm IDEA: XBRL DOCUMENT v3.19.3
Debt - Senior Unsecured Notes Payable (Details) - USD ($)
$ in Thousands
9 Months Ended
May 10, 2017
Sep. 30, 2019
Sep. 30, 2018
Debt Instrument [Line Items]      
Gross proceeds from issuance of senior notes   $ 200,000 $ 0
Senior Unsecured Notes | 5.25% Senior Notes due 2025      
Debt Instrument [Line Items]      
Debt instrument, face amount $ 300,000    
Interest rate, stated percentage 5.25%    
Gross proceeds from issuance of senior notes $ 300,000    
Net proceeds from issuance of senior notes $ 294,000    
Debt instrument, redemption price, percentage 100.00%    
Debt instrument, redemption price, percentage upon change of control 101.00%    
Senior Unsecured Notes | 5.25% Senior Notes due 2025 | Debt Instrument, Redemption, Period One      
Debt Instrument [Line Items]      
Debt instrument, redemption price, percentage 105.25%    
Senior Unsecured Notes | 5.25% Senior Notes due 2025 | Debt Instrument, Redemption, Period One | Minimum      
Debt Instrument [Line Items]      
Percentage of aggregate principal amount of notes outstanding 60.00%    
Senior Unsecured Notes | 5.25% Senior Notes due 2025 | Debt Instrument, Redemption, Period One | Maximum      
Debt Instrument [Line Items]      
Debt instrument, redemption price, percentage of principal amount 40.00%