Business Segment Information

12 Months Ended

Dec. 31, 2023

Segment Reporting Information, Additional Information [Abstract]

Business Segment Information

(16) BUSINESS SEGMENT INFORMATION

Our Chief Executive Officer, who is considered to be our CODM, reviews financial information presented on an operating segment basis for purposes of making decisions, allocating resources and assessing financial performance. Our operating segments are based on our method of internal reporting, which is generally segregated by differences in products and services. All of our operations and assets are located within the United States.

Our Electric Utilities segment includes the operating results of the regulated electric utility operations of Colorado Electric, South Dakota Electric, and Wyoming Electric, which supply regulated electric utility services to areas in Colorado, Montana, South Dakota and Wyoming. We also own and operate non-regulated power generation and mining businesses that are vertically integrated with our Electric Utilities.

Our Gas Utilities segment consists of the operating results of our regulated natural gas utility subsidiaries in Arkansas, Colorado, Iowa, Kansas, Nebraska and Wyoming.

Corporate and Other represents certain unallocated expenses for administrative activities that support our operating segments. Corporate and Other also includes business development activities that are not part of our operating segments and inter-segment eliminations.

Our CODM assesses the performance of our operating segments based on operating income. Our CODM reviews capital expenditures by operating segment rather than any individual or total asset amount. Our operating segments are equivalent to our reportable segments.

Segment information was as follows (in millions):

	Consolidating Income Statement
Year ended December 31, 2023	Electric Utilities		Gas Utilities		Corporate and Other			Total
Revenue -
External Customers	$	853.6	$	1,477.7	$	—		$	2,331.3
Inter-segment		11.4		6.5		(17.9	)		—
Total revenue		865.0		1,484.2		(17.9	)		2,331.3
Fuel, purchased power and cost of natural gas sold		200.1		783.2		(0.4	)		982.9
Operations and maintenance		236.2		328.7		(12.9	)		552.0
Depreciation, depletion and amortization		142.6		113.9		0.3			256.8
Taxes - property and production		37.3		29.6		—			66.9
Operating income (loss)	$	248.8	$	228.8	$	(4.9	)	$	472.7
Interest expense, net									(167.9	)
Other income (expense), net									(3.2	)
Income tax (expense)									(25.6	)
Net income									276.0
Net income attributable to non-controlling interest									(13.8	)
Net income available for common stock								$	262.2

	Consolidating Income Statement
Year ended December 31, 2022	Electric Utilities		Gas Utilities		Corporate and Other			Total
Revenue -
External Customers	$	888.4	$	1,663.4	$	—		$	2,551.8
Inter-segment		11.8		5.7		(17.5	)		—
Total revenue		900.2		1,669.1		(17.5	)		2,551.8
Fuel, purchased power and cost of natural gas sold		266.3		965.1		(0.8	)		1,230.6
Operations and maintenance		244.8		317.3		(13.7	)		548.4
Depreciation, depletion and amortization		135.9		114.7		0.3			250.9
Taxes - property and production		38.9		27.8		—			66.7
Operating income (loss)	$	214.3	$	244.2	$	(3.3	)	$	455.2
Interest expense, net									(161.0	)
Other income (expense), net									1.8
Income tax (expense)									(25.2	)
Net income									270.8
Net income attributable to non-controlling interest									(12.4	)
Net income available for common stock								$	258.4

	Consolidating Income Statement
Year ended December 31, 2021	Electric Utilities		Gas Utilities		Corporate and Other			Total
Revenue -
External Customers	$	830.7	$	1,118.4	$	—		$	1,949.1
Inter-segment		11.5		6.5		(18.0	)		—
Total revenue		842.2		1,124.9		(18.0	)		1,949.1
Fuel, purchased power and cost of natural gas sold		248.0		494.7		(0.8	)		741.9
Operations and maintenance		224.5		290.2		(13.0	)		501.7
Depreciation, depletion and amortization		131.5		104.2		0.3			236.0
Taxes - property and production		35.5		24.6		—			60.1
Operating income (loss)	$	202.7	$	211.2	$	(4.5	)	$	409.4
Interest expense, net									(152.4	)
Other income (expense), net									1.4
Income tax (expense)									(7.2	)
Net income									251.2
Net income attributable to non-controlling interest									(14.5	)
Net income available for common stock								$	236.7

Capital Expenditures (a) for the years ended December 31,	2023		2022		2021
Electric Utilities	$	210.7	$	243.1	$	285.8
Gas Utilities		371.9		349.5		383.3
Corporate and Other		7.3		5.1		10.5
Total capital expenditures	$	589.9	$	597.7	$	679.6

(a)Includes accruals for property, plant and equipment as disclosed in the Supplemental Cash Flow Information to the Consolidated Statement of Cash Flows.