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Debt - Senior Unsecured Notes Payable Narrative (Details) - USD ($)
12 Months Ended
May 10, 2017
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Debt Instrument [Line Items]        
Gross proceeds from issuance of senior notes   $ 200,000,000 $ 0 $ 0
Senior Unsecured Notes        
Debt Instrument [Line Items]        
Debt instrument face amount   $ 300,000,000 $ 300,000,000  
Senior Unsecured Notes | 5.25% Senior Notes due 2025        
Debt Instrument [Line Items]        
Debt instrument face amount $ 300,000,000.0      
Interest rate (percent) 5.25%      
Redemption price of notes (percent) 100.00%      
Gross proceeds from issuance of senior notes $ 300,000,000.0      
Net proceeds from issuance of senior notes $ 294,000,000.0      
Redemption price, percentage upon change of control (percent) 101.00%      
Senior Unsecured Notes | 5.25% Senior Notes due 2025 | Debt Instrument, Redemption, Period One        
Debt Instrument [Line Items]        
Redemption price of notes (percent) 105.25%      
Senior Unsecured Notes | 5.25% Senior Notes due 2025 | Debt Instrument, Redemption, Period One | Maximum        
Debt Instrument [Line Items]        
Redemption price, percentage of principal amount (percent) 40.00%      
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 (percent) 60.00%      
Senior Unsecured Notes | 5.875% Senior Notes due 2021        
Debt Instrument [Line Items]        
Interest rate (percent) 5.875%     5.875%
Redemption price of notes (percent) 102.938%     102.938%
Payments for redemption of senior notes $ 260,000,000.0