Commitments (Tables)

12 Months Ended

Dec. 31, 2022

Commitments and Contingencies Disclosure [Abstract]

Schedule of estimated commitments

									Asset
					Gas		Maintenance		Retirement		Finance and
	Coal		Nuclear Fuel		Transportation		Agreements		Obligations		Operating Leases
	(dollars in thousands)
2023	$	26,891	$	78,780	$	63,850	$	29,720	$	16,709	$	16,273
2024		26,070		39,690		62,818		57,749		52,003		15,799
2025		10,426		32,280		62,775		43,025		46,128		15,590
2026		—		28,980		68,872		15,736		49,445		15,299
2027		—		26,580		67,188		3,237		67,384		15,021
Thereafter		—		67,170		824,627		316,160		3,416,582		11,551