Other Comprehensive Income (Tables)

12 Months Ended

Dec. 31, 2019

Stockholders' Equity Note [Abstract]

Changes in Accumulated Other Comprehensive Income (Loss), Net of Tax

	Gains and Losses on Cash Flow Hedges
(Millions of Dollars)	2019		2018
Accumulated other comprehensive loss at Jan. 1	$	—	$	(0.1	)
Losses reclassified from net accumulated other comprehensive loss
Interest rate derivatives (net of taxes of $0) (a)	—		0.1
Net current period other comprehensive income	—		0.1
Accumulated other comprehensive loss at Dec. 31	$	—	$	—

^(a) 

Included in interest charges.