Shareholders' Equity and Noncontrolling Interest - Noncontrolling Interest (Details) - shares
May 04, 2017
Sep. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Noncontrolling Interest [Line Items]        
Ownership interest of non-controlling interest   6.90% 7.60%  
Common Stock Class C        
Noncontrolling Interest [Line Items]        
Common stock, shares outstanding (shares)   19,155,921   19,155,921
Common Stock Class A        
Noncontrolling Interest [Line Items]        
Common stock, shares outstanding (shares)   256,670,839   200,835,049
Subscription Agreements | Common Stock Class A        
Noncontrolling Interest [Line Items]        
Shares issued in transaction (in shares) 23,500,000