Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation - Additional Information (Details)

v3.10.0.1
Basis of Presentation - Additional Information (Details)
$ / shares in Units, $ in Thousands
9 Months Ended
Mar. 22, 2017
USD ($)
$ / shares
shares
Sep. 30, 2018
USD ($)
$ / shares
Sep. 30, 2017
USD ($)
Dec. 31, 2017
USD ($)
$ / shares
Subsidiary, Sale of Stock [Line Items]        
Contract with customer, asset, net   $ 23,300   $ 24,800
Common stock, par value (in dollars per share) | $ / shares   $ 0.001   $ 0.001
Proceeds from issuance of common stock   $ 0 $ 185,500  
Repayment of outstanding borrowings $ 71,800 61,858 164,638  
Capital expenditures $ 86,800 $ 212,152 $ 193,820  
IPO        
Subsidiary, Sale of Stock [Line Items]        
Shares of common stock sold, including shares sold by third parties (in shares) | shares 25,000,000      
Common stock, par value (in dollars per share) | $ / shares $ 0.001      
Stock price (in dollars per share) | $ / shares $ 14.00      
Proceeds from issuance of common stock $ 170,100      
Payment of underwriting discounts and commissions 10,900      
Payments of stock issuance costs, other $ 4,500      
IPO Sold By Company        
Subsidiary, Sale of Stock [Line Items]        
Shares of common stock sold, including shares sold by third parties (in shares) | shares 13,250,000      
IPO - Shares From Existing Shareholders        
Subsidiary, Sale of Stock [Line Items]        
Shares of common stock sold, including shares sold by third parties (in shares) | shares 11,750,000      
March 2017 Stock Split | IPO        
Subsidiary, Sale of Stock [Line Items]        
Stock split ratio 1.45      
Performance stock units | IPO        
Subsidiary, Sale of Stock [Line Items]        
Number of shares of outstanding stock converted (in shares) | shares 16,999,990      
Performance stock units | Series A Preferred Stock Converted To Common Stock | IPO        
Subsidiary, Sale of Stock [Line Items]        
Stock split ratio 1