SHARE-BASED PAYMENTS SHARE-BASED PAYMENTS (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	8,500,000
Number of Shares Available for Issuance	6,900,000
Maximum Value of Shares For Which Awards May Be Issued To A Participant During Any Year	$ 800
Forfeiture rate maximum (in hundredths)	3.00%
Allocated share-based compensation expense	$ 29,400	$ 46,500	$ 33,200
Tax Benefit	$ 14,100	$ 31,700	$ 12,200
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award Vesting Period	3 years
Nonvested Award, Cost Not yet Recognized, Amount	$ 16,700
Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 9 months 18 days
Nonvested, number of units	646,287	698,990
Granted, units	216,392
Released to participants, units	(240,576)
Forfeited, units	(28,519)
Nonvested, Weighted Average Grant Date Fair Value	$ 63.85	$ 54.05
Grants in Period, Weighted Average Grant Date Fair Value	76.49	$ 58.07	$ 46.94
Vested in Period, Weighted Average Grant Date Fair Value	46.58
Forfeitures, Weighted Average Grant Date Fair Value	$ 65.20
Granted in Period, Fair Value	$ 16,552	$ 15,238	$ 13,907
Vested in Period, Fair Value	$ 11,204	$ 10,691	$ 9,552
Performance-Unit Activity
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award Vesting Period	3 years
Nonvested Award, Cost Not yet Recognized, Amount	$ 25,000
Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 9 months 18 days
Nonvested, number of units	834,246	937,821
Granted, units	283,029
Released to participants, units	(300,423)
Forfeited, units	(86,181)
Nonvested, Weighted Average Grant Date Fair Value	$ 75.96	$ 66.67
Grants in Period, Weighted Average Grant Date Fair Value	88.43	$ 68.02	$ 59.57
Vested in Period, Weighted Average Grant Date Fair Value	58.99
Forfeitures, Weighted Average Grant Date Fair Value	$ 74.83
Granted in Period, Fair Value	$ 25,028	$ 23,020	$ 22,081
Vested in Period, Fair Value	$ 17,722	$ 15,018	$ 12,545
Expected Volatility Rate	21.70%	27.10%	39.20%
Expected Dividend Rate	4.87%	5.05%	5.49%
Risk Free Interest Rate	1.39%	2.47%	2.44%
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	11,600,000
Maximum allowable percentage of annual base pay withheld to purchase our common stock	10.00%
Purchase price percentage of the lower of its grant date or exercise date market price	85.00%
Employee participation in the plan (in hundredths)	68.00%	62.00%	60.00%
Shares sold under the Employee Stock Purchase Plan	359,977	171,590	165,877
Weighted Average Share Price of Shares Sold Under the Employee Stock Purchase Plan (In Dollars per Share)	$ 27.78	$ 51.24	$ 45.53
Employee Stock Award Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	900,000
Allocated share-based compensation expense	$ 200	$ 1,000	$ 200
Shares Awarded Under Employee Stock Award Program	2,871	14,022	2,553
Non-employees and Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, units	0
Options, Outstanding, Number	0

Percentage of employees enrolled in the employee stock purchase plan

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Maximum percentage estimated forfeiture rate, based on historical forfeitures, applied for all awards outstanding based on historical forfeitures under share-based payment plans.

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Employees can choose to have up to 10 percent of their annual base pay withheld to purchase our common stock, subject to terms and limitations of the plan.

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The maximum value of awards that can be issued to a participant in any year.

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The purchase price of the stock is 85 percent of the lower of its grant date or exercise date market price.

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Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Granted in Period, Fair Value

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Share price of shares sold under the employee stock purchase plan.

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Number of shares awarded under the employee stock award program

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Number of shares sold under the stock purchase plan.

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

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Aggregate number of common shares reserved for future issuance.

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

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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.

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

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of options outstanding, including both vested and non-vested options.

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