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

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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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EQUITY AND STOCK-BASED COMPENSATION - Restricted Stock Share and Restricted Stock Unit Awards, Fair Value Assumptions (Details) - $ / shares				12 Months Ended
	Mar. 21, 2019	Mar. 06, 2018	Jan. 13, 2017	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
SPX \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				1 year
SPX \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
Restricted stock shares and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual Expected Dividend Yield	0.00%	0.00%	0.00%
Vesting period				3 years
Restricted stock shares and restricted stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Correlation Between Total Shareholder Return and Individual Companies in the Composite Group or S&P Index (in dollars per share)	$ 0.1274	$ 0.1216	$ 0.1848
Restricted stock shares and restricted stock units \| Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Correlation Between Total Shareholder Return and Individual Companies in the Composite Group or S&P Index (in dollars per share)	0.4364	0.4193	0.3830
Restricted stock shares and restricted stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Correlation Between Total Shareholder Return and Individual Companies in the Composite Group or S&P Index (in dollars per share)	$ 0.7393	$ 0.6928	$ 0.5057
Restricted stock shares and restricted stock units \| Composite Group
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual Expected Stock Price Volatility	28.10%	27.90%	28.60%
Risk-free Interest Rate	2.45%	2.36%	1.50%
Restricted stock shares and restricted stock units \| SPX
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual Expected Stock Price Volatility	36.90%	42.00%	39.40%
Risk-free Interest Rate	2.45%	2.36%	1.50%