EQUITY AND STOCK-BASED COMPENSATION - Summary of Restricted Stock Share and Restricted Stock Unit Awards Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Unvested Restricted Stock Shares and Restricted Stock Units
Granted (in shares)	546
Vested (in shares)	(462)
Forfeited and other (in shares)	(261)
Outstanding at the end of period (in shares)	999
Weighted-Average Grant-Date Fair Value Per Share
Granted (in dollars per share)	$ 34.51
Vested (in dollars per share)	32.95
Forfeited and other (in dollars per share)	31.51
Outstanding at the end of period (in dollars per share)	$ 38.24
Unrecognized compensation cost related to awards with continuing operations	$ 16.1
Weighted-average period cost expected to be recognized	1 year 9 months 18 days
Restricted stock shares and restricted stock units
Unvested Restricted Stock Shares and Restricted Stock Units
Outstanding at beginning of year (in shares)	1,176	1,132	1,275
Granted (in shares)		404	486
Vested (in shares)		(312)	(358)
Forfeited and other (in shares)		(48)	(271)
Outstanding at the end of period (in shares)		1,176	1,132
Weighted-Average Grant-Date Fair Value Per Share
Outstanding at beginning of year (in dollars per share)	$ 36.40	$ 32.65	$ 37.89
Granted (in dollars per share)		48.63	35.18
Vested (in dollars per share)		39.01	42.05
Forfeited and other (in dollars per share)		33.88	49.35
Outstanding at the end of period (in dollars per share)		$ 36.40	$ 32.65
Unrecognized compensation cost	$ 16.9
Weighted-average period cost expected to be recognized	1 year 8 months 12 days

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 cost to be recognized for 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 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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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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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