XML 74 R60.htm IDEA: XBRL DOCUMENT v3.10.0.1
Debt - Schedule of Future Principal Payments and Maturities of Indebtedness (Detail) - USD ($)
$ in Millions
Jun. 30, 2018
Dec. 31, 2017
Debt Instrument [Line Items]    
2018 $ 1.7  
2019 6.8  
2020 6.8  
2021 6.8  
2022 6.8  
Thereafter 651.1  
Total debt $ 680.0 $ 1,132.3