STOCK-BASED COMPENSATION - Compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
STOCK-BASED COMPENSATION
Pre-tax expense	$ 5,207	$ 2,436	$ 9,321	$ 7,324
After tax expense	$ 3,419	$ 1,840	$ 6,525	$ 5,530

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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