The number of deferred stock units credited to members of the board during the period.

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The performance period (in years) of each PSUs.

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Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Shares Converted

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Share-Based Compensation Arrangement By Share-Based Payment Award, Performance Target, Percentage Of Shares Earned

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The number of preferred stocks designated as Series A participating preferred stocks in connection with rights agreement.

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The number of treasury shares (units) reissued during the period to satisfy equity-based compensation obligations.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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STOCKHOLDERS' EQUITY AND EQUITY INSTRUMENTS (Summary of Plan Information) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	May 31, 2015	Dec. 31, 2005
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividends paid (in dollars per share)	$ 2.88	$ 2.88	$ 2.88
Preferred stock, shares authorized (in shares)	10,000,000
Preferred stock, shares issued (in shares)	0
Preferred stock, shares Outstanding (in shares)	0
Series A preferred stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares designated as series A junior participating preferred stock (in shares)	200,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period	4 years
Award expiration period	7 years
Number of shares available from conversion (in shares)	1
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period	3 years
Number of shares available from conversion (in shares)	1
TSR PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period of PSUs	3 years
Vesting period	3 years
ROIC PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period of PSUs	3 years
Vesting period	3 years
2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares (in shares)					3,240,000
2015 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares (in shares)				3,000,000
Deferred compensation agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred stock units credited in period (in shares)	33,883	26,291	17,207
Deferred compensation agreement \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reissued from treasury stock (in shares)	9,041	6,728	6,668
Minimum \| TSR PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares earned	0.00%
Minimum \| ROIC PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares earned	0.00%
Maximum \| TSR PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares earned	150.00%
Maximum \| ROIC PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares earned	200.00%