Derivative Instruments and Hedging Activities (Narrative) (Details) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($) Interest_Rate_Swaps	Dec. 31, 2015 USD ($) Interest_Rate_Swaps	Dec. 31, 2014
Derivative [Line Items]
Available-for-sale Securities, Change in Net Unrealized Holding Gain (Loss) before Taxes	$ 2.2	$ 2.2
Effective interest rate on debt	2.572%	2.572%	2.152%
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	$ (40.9)	$ (40.9)
Net unrealized gain (loss) transferred to income statement		$ (20.9)
Current Interest Rate Swap
Derivative [Line Items]
Number of derivative instruments | Interest_Rate_Swaps	3	3
HEP | Interest Rate Contract [Member]
Derivative [Line Items]
Credit agreement advance	$ 305.0	$ 305.0
Fixed interest rate	0.74%	0.74%
Effective interest rate on debt	2.99%	2.99%
Credit agreement advance maturing in 2017	$ 150.0	$ 150.0
HEP | Current Interest Rate Swap
Derivative [Line Items]
Credit agreement advance maturing 2016	$ 155.0	$ 155.0
Fixed interest rate	0.99%	0.99%
Rate added to fixed base rate	2.25%
Effective interest rate on debt	3.24%	3.24%