Summary of Significant Accounting Policies - Redeemable common stock - (Details) - USD ($)
9 Months Ended
Feb. 29, 2016
Sep. 30, 2016
Dec. 31, 2015
Offering Costs Policy      
Offering costs $ 28,315,521 $ 28,315,521  
Underwriting discounts 27,500,000    
Deferred offering cost 17,500,000 $ 17,500,000  
Professional, filing, regulatory and other costs $ 815,521    
Class A common stock      
Redeemable Common Stock Policy      
Temporary equity outstanding   47,824,792 0
Redemption limitation, minimum net tangible assets   $ 5,000,001  
Class A common stock | Common stock      
Redeemable Common Stock Policy      
Shares issued with redemption feature   50,000,000