XML 107 R85.htm IDEA: XBRL DOCUMENT v3.8.0.1
Retirement Plans (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Retirement Benefits [Abstract]      
Defined benefit liability $ 0.5 $ 0.4  
Retirement expense $ 0.3 $ 0.1 $ 0.1