Change In Control, Term

No definition available.

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- Definition

Represents the number of stock incentive plans of the entity.

+ References

No definition available.

+ Details

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- Definition

Period in which 33% vesting rights is earned by awarded of the grant, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Represents the common stock entitled to be received under each share-based payment award.

+ References

No definition available.

+ Details

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- Definition

Share Based Compensation Arrangements by Share Based Payment Award Options, Minimum Age for Awards to Vest Immediately

+ References

No definition available.

+ Details

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- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in the third year from the date of grant, thereby giving the employee the legal right to convert the award to shares, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

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-Topic 718
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- Definition

Amount of cost capitalized for award under share-based payment arrangement.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Stock-Based Compensation Plans (Details) $ in Thousands	12 Months Ended
Stock-Based Compensation Plans (Details) $ in Thousands	Dec. 31, 2024 USD ($) stock_plan shares	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Stock compensation plans
Number of stock incentive plans \| stock_plan	3
Vesting period	3 years
Unrecognized compensation cost	$ 400
Stock-based compensation recognized in the income statement, before taxes	3,744	$ 3,298	$ 2,571
Capitalized equity-based compensation cost	$ 400	500	300
Immediate vesting for employees of certain age and above	55 years
GSWC
Stock compensation plans
Stock-based compensation recognized in the income statement, before taxes	$ 3,279	2,994	2,269
Capitalized equity-based compensation cost	400	500	300
Nonqualified stock options
Stock compensation plans
Tax benefits from exercise of stock-based awards	900	800	900
Nonqualified stock options \| GSWC
Stock compensation plans
Tax benefits from exercise of stock-based awards	900	800	900
Restricted Stock Units \| Employees and directors
Stock compensation plans
Stock-based compensation recognized in the income statement, before taxes	3,744	3,298	2,571
Restricted Stock Units \| Employees and directors \| GSWC
Stock compensation plans
Stock-based compensation recognized in the income statement, before taxes	$ 3,279	$ 2,994	$ 2,269
Performance awards
Stock compensation plans
Vesting period	3 years
2000 and 2008 Employee Plans \| Nonqualified stock options
Stock compensation plans
Percentage of rights vesting in the third year from the date of grant	34.00%
2000 and 2008 Employee Plans \| Restricted Stock Units
Stock compensation plans
Common stock entitled to be received under each award (in shares) \| shares	1
Percentage of rights vesting in the first two years from the date of grant	33.00%
Percentage of rights vesting in the third year from the date of grant	34.00%
2000 and 2008 Employee Plans \| Performance awards
Stock compensation plans
Vesting period	3 years
Percentage of rights vesting in the first two years from the date of grant	33.00%
Percentage of rights vesting in the third year from the date of grant	34.00%
2003 and 2013 Directors plans
Stock compensation plans
Vesting period	90 days
Maximum
Stock compensation plans
Chang in control, term	24 months
Weighted Average
Stock compensation plans
Expected recognition period for unrecognized compensation cost	1 year 6 months
Weighted Average \| Restricted Stock [Member]
Stock compensation plans
Expected recognition period for unrecognized compensation cost	1 year 6 months 3 days