Revenues (Tables)

3 Months Ended

Mar. 31, 2019

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue

NSP-Wisconsin’s operating revenues consists of the following:

	Three Months Ended March 31, 2019
(Millions of Dollars)	Electric		Natural Gas		All Other		Total
Major revenue types
Revenue from contracts with customers:
Residential	$	67.4	$	33.6	$	—	$	101.0
Commercial and industrial (C&I)	98.5		25.8		—		124.3
Other	1.5		—		0.1		1.6
Total retail	167.4		59.4		0.1		226.9
Interchange	44.1		—		—		44.1
Other	0.5		1.1		—		1.6
Total revenue from contracts with customers	212.0		60.5		0.1		272.6
Alternative revenue and other	3.0		0.6		—		3.6
Total revenues	$	215.0	$	61.1	$	0.1	$	276.2

	Three Months Ended March 31, 2018
(Millions of Dollars)	Electric		Natural Gas		All Other		Total
Major revenue types
Revenue from contracts with customers:
Residential	$	67.8	$	30.3	$	—	$	98.1
C&I	104.8		24.6		0.1		129.5
Other	1.6		—		0.2		1.8
Total retail	174.2		54.9		0.3		229.4
Interchange	37.7		—		—		37.7
Other	1.5		1.0		—		2.5
Total revenue from contracts with customers	213.4		55.9		0.3		269.6
Alternative revenue and other	2.9		0.6		—		3.5
Total revenues	$	216.3	$	56.5	$	0.3	$	273.1