Income Taxes (Tables)

6 Months Ended

Jun. 30, 2023

Income Tax Disclosure [Abstract]

Summary of Significant Factors Impact on Difference Between Effective Tax Rate and Federal Statutory Rate

The following table summarizes the significant factors impacting the difference between the Company's effective tax rate and the federal statutory rate for the three and six months ended June 30 (dollars in thousands):

	Three months ended June 30,										Six months ended June 30,
	2023					2022					2023					2022
Federal income taxes at statutory rates	$	2,452		21.0	%	$	2,195		21.0	%	$	12,577		21.0	%	$	14,948		21.0	%
Increase (decrease) in tax resulting from:
Flow through related to deduction of meters      and mixed service costs (1)		(5,689	)	(48.7	)		(2,401	)	(23.0	)		(19,212	)	(32.1	)		(19,835	)	(27.9	)
Tax effect of regulatory treatment of utility       plant differences		(1,525	)	(13.1	)		(976	)	(9.3	)		(5,212	)	(8.7	)		(7,298	)	(10.3	)
State income tax expense		232		2.0			78		0.7			798		1.3			901		1.3
Tax credits		(1,135	)	(9.7	)		—		—			(1,135	)	(1.9	)		—		—
Other		(145	)	(1.3	)		105		1.0			(254	)	(0.4	)		(551	)	(0.7	)
Total income tax benefit	$	(5,810	)	(49.8	)%	$	(999	)	(9.6	)%	$	(12,438	)	(20.8	)%	$	(11,835	)	(16.6	)%

(1)The Company's general rate cases included approval of base rate increases, offset by tax customer credits. As the tax customer credits are returned to customers, this results in a decrease to income tax expense as a result of flowing through the benefits related to meters and mixed service costs. The decrease in income tax expense offsets the increases in base rates granted to the Company in these general rate cases.