Quarterly report pursuant to Section 13 or 15(d)

Equity - Schedule of Common Stock Public Offerings (Detail)

v3.4.0.3
Equity - Schedule of Common Stock Public Offerings (Detail)
$ / shares in Units, shares in Thousands, $ in Millions
 3 Months Ended
Mar. 31, 2016
USD ($)
$ / shares
shares
5/4/2015 Closing Date [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Public offerings of common stock, Closing Date May 04, 2015
Public offerings of common stock, Shares Issued | shares 4,600
Public offerings of common stock, Price Per Share | $ / shares $ 18.50
Net proceeds from follow-on from public offering | $ $ 82
10/19/2015 Closing Date [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Public offerings of common stock, Closing Date Oct. 19, 2015
Public offerings of common stock, Shares Issued | shares 5,750
Public offerings of common stock, Price Per Share | $ / shares $ 18.00
Net proceeds from follow-on from public offering | $ $ 99