Share-based Compensation Arrangement by Share-based Payment Award, Award Additional Holding Period

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Contractual Term

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- Definition

The fair value estimated at the grant date.

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- Definition

Amount of difference between the fair value of the options on the date of exercise less their exercise price. The amount of taxable income to the person who exercised and a deduction to taxable income for the Company.

+ References

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Performance Period

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- Definition

Share-Based Compensation, Number Of Plans

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- Definition

Face amount per share of no-par value common stock.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Amount of tax benefit from exercise of option under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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- Definition

Number of share options (or share units) exercised during the current period.

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Stock Plans (Narrative) (Details)	3 Months Ended		12 Months Ended
Stock Plans (Narrative) (Details)	Mar. 31, 2020 $ / shares item shares	Mar. 31, 2019	Dec. 31, 2019 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of active share-based compensation plans \| item	2
Common stock, no par value \| $ / shares
Stock-Settled Stock Appreciation Rights (SSARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted
Vesting period	3 years
Options exercised			3,059
Options exercised, intrinsic value \| $			$ 10,631
Options exercised, realized tax deduction \| $			108,134
Options exercised, tax benefit \| $			$ 22,708
Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	750,000
Common stock, no par value \| $ / shares
Director Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years	3 years
Omnibus Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	750,000
Common stock, no par value \| $ / shares
Omnibus Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Omnibus Plan [Member] \| Stock-Settled Stock Appreciation Rights (SSARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term	10 years
Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Long-Term Incentive Plan [Member] \| Senior Officers and Managers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		1 year
Long-Term Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Holding period	2 years
Long-Term Incentive Plan [Member] \| Restricted Stock [Member] \| Senior Officers and Managers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	1 year
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	165,000
Number of shares issued	84,904
Award Date One [Member] \| Omnibus Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years