Other Financial Information - Change in the income tax valuation allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Regulatory Assets [Line Items]
Beginning balance	$ 23	$ 11
Additions charged to expense	235	12
Reductions charged to other accounts	(235)	0
Ending balance	23	23
Income tax valuation allowance [Member]
Regulatory Assets [Line Items]
Beginning balance	0	0
Additions charged to expense	477	0
Reductions charged to other accounts	0	0
Ending balance	$ 477	$ 0