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COMMON STOCK AND CHANGES IN CAPITALIZATION (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Jan. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Sep. 30, 2019 | Dec. 31, 2018 | May 31, 2018 | Jan. 31, 2018
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stock repurchase program, amount authorized to acquire |  |  |  |  |  |  |  |  |  |  | $ 100,000,000
Value of shares repurchased during the period |  |  |  |  |  |  |  |  | $ 200,000,000.0 |  |
Stock repurchase program, period in force | 24 months |  |  |  |  |  |  |  |  |  |
Value of shares repurchased |  | $ 89,000 | $ 2,270,000 | $ 28,330,000 | $ 5,000,000 | $ 5,000,000 | $ 99,997,000 |  |  |  |
Share purchased to satisfy tax withholding requirements (in shares) |  | 100,000 |  |  |  |  |  | 100,000 |  |  |
Shares repurchased to satisfy tax withholding requirements |  | $ 100,000 |  |  |  |  |  | $ 700,000 |  |  |
Common Stock |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares repurchased (in shares) |  | 35,977 | 296,587 | 3,618,634 | 400,597 | 412,516 | 9,692,356 |  |  |  |
Value of shares repurchased |  | $ 0 | $ 3,000 | $ 37,000 | $ 4,000 | $ 4,000 | $ 97,000 |  |  |  |
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 |
Share Repurchase Program |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares repurchased (in shares) |  |  |  |  |  |  |  |  | 20,700,000 |  |
Share Repurchase Program | Common Stock |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares repurchased (in shares) |  |  |  |  |  |  |  | 3,800,000 |  |  |
Value of shares repurchased |  |  |  |  |  |  |  | $ 30,000,000.0 |  |  |

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