CONSOLIDATED STATEMENTS OF CAPITALIZATION - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Common Stock, Par or Stated Value Per Share	$ 0	$ 0
Common stock, shares outstanding	38,151,027	36,980,612
Common stock, shares authorized	60,000,000	60,000,000
Common Shareholders' Equity:
Common shares, no par value	$ 355,143	$ 263,179
Retained earnings	564,908	512,930
Common shareholder’s equity	920,051	776,109
Long-Term Debt
Debt and Lease Obligation	643,893	579,047
Less: Current maturities	(385)	(353)
Debt Issuance Costs, Net	(3,126)	(3,139)
Long-Term Debt	640,382	575,555
Total capitalization	$ 1,560,433	$ 1,351,664
Common Stock
Common stock, shares outstanding	38,151,000	36,981,000
Common Shareholders' Equity:
Common shareholder’s equity	$ 355,143	$ 263,179
GSWC
Common Stock, Par or Stated Value Per Share	$ 0	$ 0
Common stock, shares outstanding	173.7586	171.0000
Common stock, shares authorized	1,000	1,000
Common Shareholders' Equity:
Common shares, no par value	$ 413,797	$ 370,909
Retained earnings	392,036	332,919
Common shareholder’s equity	805,833	703,828
Long-Term Debt
Debt and Lease Obligation	608,893	544,047
Less: Current maturities	(385)	(353)
Debt Issuance Costs, Net	(2,961)	(2,956)
Long-Term Debt	605,547	540,738
Total capitalization	$ 1,411,380	$ 1,244,566
GSWC | Common Stock
Common stock, shares outstanding	173.7586	171.0000
Common Shareholders' Equity:
Common shareholder’s equity	$ 413,797	$ 370,909
6.81% notes due 2028
Long-Term Debt
Debt and Lease Obligation	$ 15,000	$ 15,000
Interest rate per annum (as a percent)	6.81%	6.81%
6.81% notes due 2028 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 15,000	$ 15,000
Interest rate per annum (as a percent)	6.81%	6.81%
6.59% notes due 2029
Long-Term Debt
Debt and Lease Obligation	$ 40,000	$ 40,000
Interest rate per annum (as a percent)	6.59%	6.59%
6.59% notes due 2029 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 40,000	$ 40,000
Interest rate per annum (as a percent)	6.59%	6.59%
7.875% notes due 2030
Long-Term Debt
Debt and Lease Obligation	$ 20,000	$ 20,000
Interest rate per annum (as a percent)	7.875%	7.875%
7.875% notes due 2030 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 20,000	$ 20,000
Interest rate per annum (as a percent)	7.875%	7.875%
7.23% notes due 2031
Long-Term Debt
Debt and Lease Obligation	$ 50,000	$ 50,000
Interest rate per annum (as a percent)	7.23%	7.23%
7.23% notes due 2031 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 50,000	$ 50,000
Interest rate per annum (as a percent)	7.23%	7.23%
6.00% notes due 2041
Long-Term Debt
Debt and Lease Obligation	$ 62,000	$ 62,000
Interest rate per annum (as a percent)	6.00%	6.00%
6.00% notes due 2041 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 62,000	$ 62,000
Interest rate per annum (as a percent)	6.00%	6.00%
3.45% notes due 2029
Long-Term Debt
Debt and Lease Obligation	$ 15,000	$ 15,000
Interest rate per annum (as a percent)	3.45%	3.45%
3.45% notes due 2029 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 15,000	$ 15,000
Interest rate per annum (as a percent)	3.45%	3.45%
5.87% notes due 2028
Long-Term Debt
Debt and Lease Obligation	$ 40,000	$ 40,000
Interest rate per annum (as a percent)	5.87%	5.87%
5.87% notes due 2028 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 40,000	$ 40,000
Interest rate per annum (as a percent)	5.87%	5.87%
2.17% notes due 2030
Long-Term Debt
Debt and Lease Obligation	$ 85,000	$ 85,000
Interest rate per annum (as a percent)	2.17%	2.17%
2.17% notes due 2030 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 85,000	$ 85,000
Interest rate per annum (as a percent)	2.17%	2.17%
2.90% notes due 2040
Long-Term Debt
Debt and Lease Obligation	$ 75,000	$ 75,000
Interest rate per annum (as a percent)	2.90%	2.90%
2.90% notes due 2040 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 75,000	$ 75,000
Interest rate per annum (as a percent)	2.90%	2.90%
4.548% note due 2032
Long-Term Debt
Debt and Lease Obligation	$ 17,500	$ 17,500
Interest rate per annum (as a percent)	4.548%	4.548%
4.949% note due 2037
Long-Term Debt
Debt and Lease Obligation	$ 17,500	$ 17,500
Interest rate per annum (as a percent)	4.949%	4.949%
5.12% notes due 2033
Long-Term Debt
Debt and Lease Obligation	$ 100,000	$ 100,000
Interest rate per annum (as a percent)	5.12%	5.12%
5.12% notes due 2033 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 100,000	$ 100,000
Interest rate per annum (as a percent)	5.12%	5.12%
5.22 % note due 2038
Long-Term Debt
Debt and Lease Obligation	$ 30,000	$ 30,000
Interest rate per annum (as a percent)	5.22%	5.22%
5.22 % note due 2038 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 30,000	$ 30,000
Interest rate per annum (as a percent)	5.22%	5.22%
5.50% notes due 2027
Long-Term Debt
Debt and Lease Obligation	$ 65,000	$ 0
Interest rate per annum (as a percent)	5.50%
5.50% notes due 2027 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 65,000	0
Interest rate per annum (as a percent)	5.50%
5.50% notes due 2026
Long-Term Debt
Debt and Lease Obligation	$ 7,730	$ 7,730
Interest rate per annum (as a percent)	5.50%	5.50%
5.50% notes due 2026 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 7,730	$ 7,730
Interest rate per annum (as a percent)	5.50%	5.50%
State Water Project due 2035
Long-Term Debt
Debt and Lease Obligation	$ 1,807	$ 1,729
State Water Project due 2035 | GSWC
Long-Term Debt
Debt and Lease Obligation	1,807	1,729
American Recovery and Reinvestment Act Obligation due 2033
Long-Term Debt
Debt and Lease Obligation	2,356	2,588
American Recovery and Reinvestment Act Obligation due 2033 | GSWC
Long-Term Debt
Debt and Lease Obligation	$ 2,356	$ 2,588