XML 85 R74.htm IDEA: XBRL DOCUMENT v3.19.1
Fair Value Measurements (Details) - USD ($)
$ in Millions
Mar. 31, 2019
Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available-for-sale securities, amortized cost basis $ 73.5 $ 55.4
investments, fair value 73.6 55.1
Reported Value Measurement    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Long-term debt, fair value disclosure 131.5 130.0
Estimate of Fair Value Measurement    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Long-term debt, fair value disclosure $ 144.7 $ 139.0