Business Segment (Tables)

9 Months Ended

Sep. 30, 2020

Segment Reporting [Abstract]

Summary of Information by Business Segment

			Three Months Ended
			September 30, 2020				September 30, 2019
	Total Assets at		External Revenues		Income (Loss)		External Revenues		Income (Loss)
(Millions of dollars)	September 30, 2020
Marketing	$	2,358.1	$	2,839.1	$	81.7	$	3,657.6	$	94.0
Corporate and other assets	430.1		(0.1)		(14.8)		—		(24.8)
Total	$	2,788.2	$	2,839.0	$	66.9	$	3,657.6	$	69.2

	Nine Months Ended
	September 30, 2020				September 30, 2019
	External Revenues		Income (Loss)		External Revenues		Income (Loss)
(Millions of dollars)
Marketing	$	8,403.4	$	362.2	$	10,574.3	$	154.7
Corporate and other assets	—		(37.1)		0.1		(47.5)
Total	$	8,403.4	$	325.1	$	10,574.4	$	107.2