STOCK-BASED COMPENSATION - Plan Information and P&L Impact (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) plan shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
STOCK-BASED COMPENSATION
Number of active plans \| plan	2
Term of plan	10 years
Income tax benefit related to non-cash compensation \| $	$ 11.4	$ 12.2	$ 11.2
Excess tax benefit \| $	$ 2.5	$ 17.1	$ 77.6
Equity Award Plan
STOCK-BASED COMPENSATION
Number of shares authorized \| shares	6,100,000
Inducement Plan
STOCK-BASED COMPENSATION
Number of shares authorized \| shares	500,000

Represents the number of active plans under which future awards may be granted.

No definition available.

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- Definition

The period of time, from the grant date until the time at which the share-based [option] award expires.

+ References

No definition available.

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The aggregate cash inflow comprised of the amount received from (a) employees to acquire the entity's shares under incentive awards, including stock option exercises and restricted stock arrangements, and (b) the excess tax benefit arising from such transactions.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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