Chang in control, term

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- Definition

Represents the number of stock incentive plans of the entity.

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No definition available.

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- Definition

Period in which 33% vesting rights is earned by awardeed 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.

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- Definition

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

+ References

No definition available.

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- Definition

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

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No definition available.

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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.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

+ References

No definition available.

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Stock-Based Compensation Plans (Details) $ in Thousands	12 Months Ended
Stock-Based Compensation Plans (Details) $ in Thousands	Dec. 31, 2019 USD ($) stock_plan shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Stock compensation plans
Number of stock incentive plans \| stock_plan	3
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 245
Stock-based compensation recognized in the income statement, before taxes	$ 2,517	$ 3,851	$ 2,885
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	$ 2,253	3,397	2,420
Capitalized equity-based compensation cost	265	199	195
Nonqualified stock options
Stock compensation plans
Tax benefits from exercise of stock-based awards	1,800	1,600	1,000
Nonqualified stock options \| GSWC
Stock compensation plans
Tax benefits from exercise of stock-based awards	1,800	1,600	1,000
Restricted Stock Units \| Employees and directors
Stock compensation plans
Stock-based compensation recognized in the income statement, before taxes	2,517	3,851	2,885
Restricted Stock Units \| Employees and directors \| GSWC
Stock compensation plans
Stock-based compensation recognized in the income statement, before taxes	$ 2,253	$ 3,397	$ 2,420
Performance awards
Stock compensation plans
Vesting period	3 years
2000 and 2008 Employee Plans \| Nonqualified stock options
Stock compensation plans
Vesting period	3 years
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 \| 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 [Member]
Stock compensation plans
Vesting period	90 days
Maximum
Stock compensation plans
Chang in control, term	P24M
Weighted Average [Member]
Stock compensation plans
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 25 days
Weighted Average [Member] \| Restricted Stock [Member]
Stock compensation plans
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 6 months 18 days