Selected Balance Sheet Data

9 Months Ended

Sep. 30, 2020

Balance Sheet Related Disclosures [Abstract]

Selected Balance Sheet Data

(Millions of Dollars)	Sept. 30, 2020		Dec. 31, 2019
Accounts receivable, net
Accounts receivable	$	117.9	$	98.0
Less allowance for bad debts	(7.1)		(5.3)
Accounts receivable, net	$	110.8	$	92.7

(Millions of Dollars)	Sept. 30, 2020		Dec. 31, 2019
Inventories
Materials and supplies	$	26.2	$	24.7
Fuel	7.0		6.3
Total inventories	$	33.2	$	31.0

(Millions of Dollars)	Sept. 30, 2020		Dec. 31, 2019
Property, plant and equipment, net
Electric plant	$	8,751.8	$	8,453.0
Construction work in progress	1,075.1		485.4
Total property, plant and equipment	9,826.9		8,938.4
Less accumulated depreciation	(2,458.4)		(2,306.8)
Property, plant and equipment, net	$	7,368.5	$	6,631.6