Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the 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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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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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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STOCK-BASED COMPENSATION (Narrative) (Details) - USD ($) shares in Thousands		3 Months Ended
	Mar. 31, 2019	Mar. 31, 2019	Mar. 31, 2018	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation		$ 5,800,000	$ 3,100,000
Income tax benefit		1,100,000	$ 900,000
Authorized common stock repurchase amount	$ 600,000,000	$ 600,000,000
Repurchases of common stock (in shares)	5,700	97	280
Repurchases of common stock	$ 300,300,000	$ 6,324,000	$ 14,264,000
Remaining amount for repurchase under program				$ 299,700,000
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	23,100,000	$ 23,100,000
Period for recognition (in years)		2 years 7 months
Fair value restricted stock		$ 3,200,000	1,300,000
Performance stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 4,600,000	4,600,000
Fair value restricted stock		$ 2,900,000	$ 500,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)		3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)		5 years