BASIS OF PRESENTATION - Adoption of 2020-06 (Details) - USD ($) $ in Thousands |
Sep. 30, 2021 |
Dec. 31, 2020 |
---|---|---|
New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
Deferred tax liabilities | $ 70,325 | $ 16,190 |
Long-term convertible securities | 563,697 | 474,834 |
Retained earnings | $ 653,184 | 532,265 |
Cumulative Effect, Period of Adoption, Adjustment | ||
New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
Deferred tax liabilities | (20,600) | |
Retained earnings | (2,800) | |
Additional paid-in capital | (63,300) | |
Cumulative Effect, Period of Adoption, Adjustment, Debt Discount Reclassification | ||
New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
Long-term convertible securities | 89,100 | |
Cumulative Effect, Period of Adoption, Adjustment, Debt Discount Amortization and Equity Costs Reclassification | ||
New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
Long-term convertible securities | $ (2,500) |