CONSOLIDATED STATEMENTS OF CAPITALIZATION (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Capitalization, Long-term Debt and Equity	$ 815,278	$ 786,845
Common stock, shares authorized	60,000,000	60,000,000
Common stock, shares outstanding	36,571,360	36,501,914
GSWC
Capitalization, Long-term Debt and Equity	$ 767,751	$ 744,630
Common stock, shares authorized	1,000	1,000
Common stock, shares outstanding	146	146
6.87% notes due 2023 \| GSWC
Interest rate per annum (as a percent)	6.87%
7.00% notes due 2023 \| GSWC
Interest rate per annum (as a percent)	7.00%
6.81% notes due 2028
Interest rate per annum (as a percent)	6.81%	6.81%
6.81% notes due 2028 \| GSWC
Interest rate per annum (as a percent)	6.81%	6.81%
6.59% notes due 2029
Interest rate per annum (as a percent)	6.59%	6.59%
6.59% notes due 2029 \| GSWC
Interest rate per annum (as a percent)	6.59%	6.59%
7.875% notes due 2030
Interest rate per annum (as a percent)	7.875%	7.875%
7.875% notes due 2030 \| GSWC
Interest rate per annum (as a percent)	7.875%	7.875%
7.23% notes due 2031
Interest rate per annum (as a percent)	7.23%	7.23%
7.23% notes due 2031 \| GSWC
Interest rate per annum (as a percent)	7.23%	7.23%
6.00% notes due 2041
Interest rate per annum (as a percent)	6.00%	6.00%
6.00% notes due 2041 \| GSWC
Interest rate per annum (as a percent)	6.00%	6.00%
3.45% private placement notes due 2029
Interest rate per annum (as a percent)	3.45%	3.45%
3.45% private placement notes due 2029 \| GSWC
Interest rate per annum (as a percent)	3.45%	3.45%
9.56% private placement notes due 2031
Interest rate per annum (as a percent)	9.56%	9.56%
9.56% private placement notes due 2031 \| GSWC
Interest rate per annum (as a percent)	9.56%	9.56%
5.87% private placement notes due 2028
Interest rate per annum (as a percent)	5.87%	5.87%
5.87% private placement notes due 2028 \| GSWC
Interest rate per annum (as a percent)	5.87%	5.87%
6.70% private placement notes due 2019
Interest rate per annum (as a percent)	6.70%	6.70%
6.70% private placement notes due 2019 \| GSWC
Interest rate per annum (as a percent)	6.70%	6.70%
5.50% tax-exempt obligation due 2026
Interest rate per annum (as a percent)	5.50%	5.50%
5.50% tax-exempt obligation due 2026 \| GSWC
Interest rate per annum (as a percent)	5.50%	5.50%

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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-Name Accounting Standards Codification
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