Stockholders' Equity and Partners' Capital - Narrative (Details) - USD ($)
1 Months Ended 9 Months Ended
Aug. 31, 2017
Feb. 29, 2016
Sep. 30, 2017
Subsidiary, Sale of Stock [Line Items]      
Shares withheld for taxes     400,000
Shares withheld for taxes, value     $ 3,500,000
Stock repurchase program, authorized amount $ 250,000,000 $ 200,000,000  
Stock repurchase program, period in force (in months) 18 months 18 months  
Stock repurchased during period (in shares)   26,337,295 2,482,570
Stock repurchased, weighted average price (in dollars per share)   $ 7.59 $ 8.75
Stock repurchase program, remaining authorized repurchase amount     $ 228,300,000
Stock repurchased, fees acquired   $ 500,000 $ 49,700
ATM Program, November 2016      
Subsidiary, Sale of Stock [Line Items]      
Issuance of common shares (in shares)     0
Gross proceeds capacity remaining     $ 500,000,000