Revenue (Tables)

12 Months Ended

Dec. 31, 2020

Revenue from Contract with Customer [Abstract]

The following tables depict the disaggregation of revenue, including intercompany revenue, from contracts with customers by customer type and timing of revenue recognition for each of the reportable segments, for the years ended December 31, 2020, 2019 and 2018. Sales tax and other similar taxes are excluded from revenues.


Year ended December 31, 2020	Electric Utilities		Gas Utilities		Power Generation		Mining		Inter-company Revenues		Total
Customer types:	(in thousands)
Retail	$	610,721	$	765,922	$	—	$	58,567	$	(31,478)	$	1,403,732
Transportation	—		154,581		—		—		(526)		154,055
Wholesale	17,848		—		103,258		—		(97,169)		23,937
Market - off-system sales	24,309		260		—		—		(8,797)		15,772
Transmission/Other	58,965		43,658		—		—		(19,315)		83,308
Revenue from contracts with customers	711,843		964,421		103,258		58,567		(157,285)		1,680,804
Other revenues	2,201		10,249		1,789		2,508		(610)		16,137
Total revenues	$	714,044	$	974,670	$	105,047	$	61,075	$	(157,895)	$	1,696,941

Timing of revenue recognition:
Services transferred at a point in time	$	—	$	—	$	—	$	58,567	$	(31,478)	$	27,089
Services transferred over time	711,843		964,421		103,258		—		(125,807)		1,653,715
Revenue from contracts with customers	$	711,843	$	964,421	$	103,258	$	58,567	$	(157,285)	$	1,680,804


Year ended December 31, 2019	Electric Utilities		Gas Utilities		Power Generation		Mining		Inter-company Revenues		Total
Customer types:	(in thousands)
Retail	$	605,756	$	817,840	$	—	$	59,233	$	(32,053)	$	1,450,776
Transportation	—		143,390		—		—		(1,042)		142,348
Wholesale	20,884		—		99,157		—		(91,577)		28,464
Market - off-system sales	23,817		691		—		—		(7,736)		16,772
Transmission/Other	57,104		47,725		—		—		(16,797)		88,032
Revenue from contracts with customers	707,561		1,009,646		99,157		59,233		(149,205)		1,726,392
Other revenues	5,191		384		2,101		2,396		(1,564)		8,508
Total revenues	$	712,752	$	1,010,030	$	101,258	$	61,629	$	(150,769)	$	1,734,900

Timing of revenue recognition:
Services transferred at a point in time	$	—	$	—	$	—	$	59,233	$	(32,053)	$	27,180
Services transferred over time	707,561		1,009,646		99,157		—		(117,152)		1,699,212
Revenue from contracts with customers	$	707,561	$	1,009,646	$	99,157	$	59,233	$	(149,205)	$	1,726,392


Year ended December 31, 2018	Electric Utilities		Gas Utilities		Power Generation		Mining		Inter-company Revenues		Total
Customer types:	(in thousands)
Retail	$	594,329	$	833,379	$	—	$	65,803	$	(32,194)	$	1,461,317
Transportation	—		140,705		—		—		(1,348)		139,357
Wholesale	33,687		—		90,791		—		(84,957)		39,521
Market - off-system sales	24,799		866		—		—		(8,102)		17,563
Transmission/Other	56,209		49,402		—		—		(14,827)		90,784
Revenue from contracts with customers	709,024		1,024,352		90,791		65,803		(141,428)		1,748,542
Other revenues	2,427		955		1,660		2,230		(1,546)		5,726
Total revenues	$	711,451	$	1,025,307	$	92,451	$	68,033	$	(142,974)	$	1,754,268

Timing of revenue recognition:
Services transferred at a point in time	$	—	$	—	$	—	$	65,803	$	(32,194)	$	33,609
Services transferred over time	709,024		1,024,352		90,791		—		(109,234)		1,714,933
Revenue from contracts with customers	$	709,024	$	1,024,352	$	90,791	$	65,803	$	(141,428)	$	1,748,542