Consolidated Balance Sheets (Parenthetical) - $ / shares
Sep. 30, 2016
Dec. 31, 2015
Statement of Financial Position [Abstract]    
Common stock, par value per share (in USD per share) $ 0.01 $ 0.01
Common stock, shares authorized (in shares) 750,000,000 750,000,000
Common stock, shares issued (in shares) 483,566,341 441,819,964
Common stock, shares outstanding (in shares) 483,566,341 441,819,964