Commitment and Contingencies Wind Operating Commitments (Details)	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Wind operating commitments, minimum net capacity factor	48.00%

Wind operating commitments, minimum net capacity factor

No definition available.

Name:	sps_WindOperatingCommitmentsMinimumNetCapacityFactor
Namespace Prefix:	sps_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant