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v3.20.2

Stock-based Compensation - Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
May 07, 2014 | Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Stock-based Compensation |  |  |  |  |  |
Unrecognized compensation cost |  | $ 29,100 |  | $ 29,100 |  |
Equity Incentive Plan 2010 |  |  |  |  |  |
Shares |  |  |  |  |  |
Granted (in shares) | 0 |  |  |  |  |
Equity Incentive Plan 2014 |  |  |  |  |  |
Stock-based Compensation |  |  |  |  |  |
Number of shares authorized |  | 4,860,870 |  | 4,860,870 |  |
Employee and Directors Stock Options |  |  |  |  |  |
Stock-based Compensation |  |  |  |  |  |
Stock-based compensation |  | $ 0 | $ 0 | $ 0 | $ 0 |
Unrecognized compensation cost |  | $ 0 |  | $ 0 |  |
Shares |  |  |  |  |  |
Balance at the beginning of the period (in shares) |  |  |  | 364,153 |  |
Exercised (in shares) |  |  |  | (244,153) |  |
Balance at the end of the period (in shares) |  | 120,000 |  | 120,000 |  | 364,153
Vested and exercisable at the end of the period (in shares) |  | 120,000 |  | 120,000 |  |
Exercise Price |  |  |  |  |  |
Balance at the beginning of the period (in dollars per share) |  |  |  | $ 22.90 |  |
Exercised (in dollars per share) |  |  |  | 20.00 |  |
Balance at the end of the period (in dollars per share) |  | $ 28.80 |  | 28.80 |  | $ 22.90
Vested and exercisable at the end of the period (in dollars per share) |  | $ 28.80 |  | $ 28.80 |  |
Remaining Contractual Term |  |  |  |  |  |
Remaining Contractual Term (in years) |  |  |  | 6 months 25 days |  | 9 months
Vested and exercisable |  |  |  | 6 months 25 days |  |
Aggregate Intrinsic Value |  |  |  |  |  |
Balance at the beginning of the period |  |  |  | $ 8,965 |  |
Exercised |  |  |  | 3,078 |  |
Balance at the end of the period |  | $ 74 |  | 74 |  | $ 8,965
Vested and exercisable at the end of the period |  | 74 |  | 74 |  |
Restricted Stock Units |  |  |  |  |  |
Stock-based Compensation |  |  |  |  |  |
Stock-based compensation |  | $ 6,600 | $ 4,900 | $ 15,000 | $ 14,900 |

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- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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