SHARE-BASED COMPENSATION - Additional information related to share-based compensation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Liability for cash-settled restricted stock units	$ 13,273	$ 21,731
Restricted Stock and Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation expense	47,789	52,218	$ 54,011
Tax benefits associated with share-based compensation expense	8,061	8,913	7,772
Liability for cash-settled restricted stock units	50,757	51,206	50,750
Unrecognized share-based compensation expense	$ 74,014	$ 75,770	$ 87,341
Expected weighted average period associated with the recognition of unrecognized share-based compensation expense	2 years 4 months 24 days	2 years 3 months 18 days	2 years 4 months 24 days
Cash Settled \| Restricted Stock and Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Liability for cash-settled restricted stock units	$ 13,273	$ 21,731	$ 20,648

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Name Accounting Standards Codification
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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

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

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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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