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COMMON STOCK AND CHANGES IN CAPITALIZATION (Details) - USD ($) | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Jan. 31, 2019 | May 31, 2018 | Jan. 31, 2018
Class of Stock [Line Items] |  |  |  |  |
Stock repurchase program, amount authorized to acquire |  |  | $ 400,000,000.0 |  | $ 100,000,000
Stock repurchase program, period in force | 24 months |  |  |  |
Amount of shares repurchased | $ 28,200,000 |  |  |  |
Restricted Stock |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Shares repurchased to satisfy tax withholding requirements | $ 100,000 |  |  |  |
Common Stock |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Shares repurchased (in shares) | 3,618,634 | 9,692,356 |  |  |
Minimum |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Stock repurchase program, amount authorized to acquire |  |  |  | $ 100,000,000 |
Maximum |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Stock repurchase program, amount authorized to acquire |  |  |  | $ 200,000,000 |

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