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- Definition

Aggregate value of stock related to awards to be issued in future

+ References

No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

+ References

No definition available.

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- Definition

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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- 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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STOCK-BASED COMPENSATION (Retricted Stock and Restricted Stock Units Additional Information) (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	Mar. 15, 2018	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019
Equity classified award \| Performance targets \| Equity-settled award \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			$ 1.0
Unrecognized compensation cost, period for recognition			2 years 8 months 12 days
Equity classified award \| Performance targets \| Equity-settled award \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			$ 3.6
Unrecognized compensation cost, period for recognition			2 years 9 months 18 days
Equity classified award \| Service period \| Equity-settled award \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			$ 0.8
Unrecognized compensation cost, period for recognition			1 year 8 months 12 days
Equity classified award \| Service period \| Equity-settled award \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			$ 76.3
Unrecognized compensation cost, period for recognition			2 years 8 months 12 days
Liability classified award \| Service period \| Cash-settled award \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			$ 32.3
Unrecognized compensation cost, period for recognition			2 years 3 months 18 days
Liability classified award \| Service period \| Cash-settled award \| Restricted stock units \| Accrued compensation and benefits expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Liability associated with stock-based awards current			$ 26.8	$ 21.9
2020 Acquisitions \| Performance targets \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			$ 0.5
Unrecognized compensation cost, period for recognition			2 years
Estimated future operating results, period			2 years
Vesting period (in years)			3 years
Future value of awards			$ 11.5
2019 Acquisitions \| Equity classified award \| Performance targets \| Equity-settled award \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated future operating results, period				12 months
Vesting period (in years)				4 years
Continuum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated future operating results, period	12 months
Continuum \| Equity classified award \| Performance targets \| Equity-settled award \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award accelerated compensation cost		$ 0.8