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v3.20.4

Changes In Capitalization (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jan. 31, 2019 | Dec. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | May 31, 2018 | Jan. 31, 2018
Class of Stock [Line Items] |  |  |  |  |  |  |
Stock repurchase program, authorized amount |  |  |  |  |  | $ 200,000,000 | $ 100,000,000
Stock repurchase program, additional authorized amount |  |  |  |  |  | $ 100,000,000 |
Stock repurchased and retired during period (in shares) |  |  |  |  | 20,700,000 |  |
Stock repurchased and retired during period, net of tax |  |  |  |  | $ 200,000,000.0 |  |
Stock repurchase program, period in force | 24 months |  |  |  |  |  |
Value of shares repurchased |  |  | $ 236,000 | $ 30,688,000 | $ 200,251,000 |  |
Share purchased to satisfy tax withholding requirements (in shares) |  |  | 200,000 | 100,000 |  |  |
Tax withholding requirement |  |  | $ 200,000 | $ 700,000 |  |  |
Common Stock |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Stock repurchased and retired during period (in shares) |  |  | 243,054 | 3,951,198 | 20,746,536 |  |
Value of shares repurchased |  |  | $ 3,000 | $ 40,000 | $ 207,000 |  |
Share Repurchase Program | Common Stock |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Stock repurchased and retired during period (in shares) |  | 0 |  | 3,800,000 |  |  |
Value of shares repurchased |  |  |  | $ 30,000,000 |  |  |

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