3. Fair Value Investments (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Investments	$ 92.8	$ 86.5
Total long-term debt, excluding leases and current maturities	422.5	421.9
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Investments	984.2	843.2
Total long-term debt, excluding leases and current maturities	$ 454.2	$ 454.3