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Amount of cost for defined contribution plan.

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

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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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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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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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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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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Purchase price of common stock expressed as a percentage of its fair value.

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STOCK-BASED COMPENSATION PLANS - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
STOCK-BASED COMPENSATION PLANS:
Options outstanding (in shares)	375,000
Weighted average exercise price of options (in dollars per share)	$ 31.08
Weighted average remaining contractual life of options	6 years
Stock Based Compensation Plans
STOCK-BASED COMPENSATION PLANS:
Compensation expense	$ 33,000,000	$ 26,000,000	$ 19,000,000
ESPP
STOCK-BASED COMPENSATION PLANS:
Number of shares reserved for award (in shares)	3,200,000
Compensation expense	$ 1,000,000	1,000,000	1,000,000
Number of shares available for future grant (in shares)	520,052
ESPP \| Maximum
STOCK-BASED COMPENSATION PLANS:
Percentage of the fair market value of common stock as of the first day of the quarter or on last day of the quarter	85.00%
RSAs
STOCK-BASED COMPENSATION PLANS:
Compensation expense	$ 9,000,000	5,000,000	3,000,000
Unrecognized compensation expense	$ 8,000,000
Unrestricted shares granted (in shares)	287,550
Stock Grants \| Non Employee Director
STOCK-BASED COMPENSATION PLANS:
Compensation expense	$ 1,000,000	$ 1,000,000	$ 1,000,000
Unrestricted shares granted (in shares)	24,000	20,000	20,000
SARs
STOCK-BASED COMPENSATION PLANS:
Compensation expense	$ 4,000,000	$ 3,000,000	$ 7,000,000
SARs term	10 years
SAR's outstanding (in shares)	2,080,032	3,060,000
SAR's outstanding intrinsic value	$ 27,000,000
SAR's remaining contractual life	4 years
SARs \| Minimum
STOCK-BASED COMPENSATION PLANS:
Vesting period	0 years
SARs \| Maximum
STOCK-BASED COMPENSATION PLANS:
Vesting period	4 years
Stock Options
STOCK-BASED COMPENSATION PLANS:
Compensation expense	$ 0	$ 0	0
SAR's outstanding intrinsic value	1,000,000
401 (K) Plan
STOCK-BASED COMPENSATION PLANS:
Compensation expense relating to match	$ 17,000,000	$ 16,000,000	$ 7,000,000
Number of shares reserved for matches (in shares)	7,000,000
Number of shares available for future grants (in shares)	3,575,958
Class A Common Stock \| LTIP
STOCK-BASED COMPENSATION PLANS:
Number of shares reserved for award (in shares)	14,000,000
Number of shares (including forfeited shares) available for future grants	4,968,511
Award Date 2019 \| RSAs \| LTIP
STOCK-BASED COMPENSATION PLANS:
Vesting period	2 years
Percentage of restriction to be lapsed in year one from grant date	50.00%
Percentage of restriction to be lapsed in year two from grant date	50.00%
Award Date, 2018 \| RSAs \| LTIP
STOCK-BASED COMPENSATION PLANS:
Vesting period		2 years
Percentage of restriction to be lapsed in year one from grant date		50.00%
Percentage of restriction to be lapsed in year two from grant date		50.00%
Award Date, 2017 \| RSAs \| LTIP
STOCK-BASED COMPENSATION PLANS:
Vesting period			2 years
Percentage of restriction to be lapsed in year one from grant date			50.00%
Percentage of restriction to be lapsed in year two from grant date			50.00%