Segment Information (Tables)

6 Months Ended

Jun. 30, 2025

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]

Financial data for the reportable segments are as follows (in thousands):

Three Months Ended
June 30, 2025	Electric		Gas		Total
Operating revenues	$	279,468	$	63,245	$	342,713
Fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion shown separately below)	59,603		15,668		75,271
Operating, general, and administrative	73,615		22,773		96,388
Property and other taxes	37,318		10,850		48,168
Depreciation and depletion	52,387		9,992		62,379
Interest expense, net	(27,562)		(7,297)		(34,859)
Other income, net	121		456		577
Income tax (expense) benefit	(4,230)		201		(4,029)
Segment net income	$	24,874	$	(2,678)	$	22,196
Reconciliation to consolidated net income
Other, net(1)					(968)
Consolidated net income					$	21,228

Three Months Ended
June 30, 2024	Electric		Gas		Total
Operating revenues	$	260,134	$	59,795	$	319,929
Fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion shown separately below)	60,887		15,593		76,480
Operating, general, and administrative	66,761		21,721		88,482
Property and other taxes	28,006		8,251		36,257
Depreciation and depletion	47,546		9,387		56,933
Interest expense, net	(23,298)		(7,147)		(30,445)
Other income, net	4,031		927		4,958
Income tax (expense) benefit	(3,891)		304		(3,587)
Segment net income	$	33,776	$	(1,073)	$	32,703
Reconciliation to consolidated net income
Other, net(1)					(1,049)
Consolidated net income					$	31,654

Six Months Ended
June 30, 2025	Electric		Gas		Total
Operating revenues	$	614,951	$	194,392	$	809,343
Fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion shown separately below)	152,355		61,113		213,468
Operating, general, and administrative	146,094		47,943		194,037
Property and other taxes	70,604		20,645		91,249
Depreciation and depletion	104,875		19,904		124,779
Interest expense, net	(55,318)		(14,331)		(69,649)
Other income, net	2,611		1,547		4,158
Income tax expense	(14,102)		(4,226)		(18,328)
Segment net income	$	74,214	$	27,777	$	101,991
Reconciliation to consolidated net income
Other, net(1)					(3,823)
Consolidated net income					$	98,168

Six Months Ended
June 30, 2024	Electric		Gas		Total
Operating revenues	$	603,320	$	191,951	$	795,271
Fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion shown separately below)	176,228		74,973		251,201
Operating, general, and administrative	134,979		45,650		180,629
Property and other taxes	64,306		19,120		83,426
Depreciation and depletion	94,850		18,826		113,676
Interest expense, net	(47,955)		(13,396)		(61,351)
Other income, net	9,492		1,981		11,473
Income tax expense	(11,174)		(2,869)		(14,043)
Segment net income	$	83,320	$	19,098	$	102,418
Reconciliation to consolidated net income
Other, net(1)					(5,678)
Consolidated net income					$	96,740