Debt - Senior Unsecured Notes (Details) - USD ($)
Aug. 18, 2016
Sep. 30, 2016
Dec. 31, 2015
Debt Instrument [Line Items]      
Unamortized deferred financing costs   $ 38,812,000 $ 41,577,000
Senior Unsecured Notes      
Debt Instrument [Line Items]      
Aggregate principal amount of debt $ 300,000,000    
Stated interest rates 4.45%    
Debt issuance, percentage of principal amount 99.378%    
Proceeds from issuance of debt, net of transaction fees and expenses $ 296,200,000    
Deferred financing costs $ 3,000,000    
Unamortized deferred financing costs   $ 2,900,000  
Period Prior to June 15, 2026 | Senior Unsecured Notes      
Debt Instrument [Line Items]      
Redemption price, percent of principal amount 100.00%