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Stockholders' Equity (Narratives) (Details) - USD ($) |  |  | 1 Months Ended | 3 Months Ended |
--- | --- | --- | --- | --- | ---
Nov. 07, 2019 | Nov. 08, 2018 | Feb. 29, 2020 | Sep. 30, 2020 | Sep. 30, 2019 | Nov. 02, 2018
Class Of Stock [Line Items] |  |  |  |  |  |
Stock repurchase, authorized amount |  |  | $ 100,000,000.0 |  |  | $ 60,000,000.0
Maximum amount of common stock may be repurchased in calendar year |  |  |  |  |  | $ 30,000,000.0
Stock repurchase, increase in authorized amount |  |  | $ 40,000,000.0 |  |  |
Stock repurchase, extended period |  |  | 3 years |  |  |
Stock repurchase, extended period, effective date |  |  | Feb. 05, 2020 |  |  |
Total number of shares repurchased |  |  |  | 0 | 0 |
2013 Equity Incentive Plan |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Increase in authorized shares for issuance | 7,000,000.0 |  |  |  |  |
2014 Employee Stock Purchase Plan |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Increase in authorized shares for issuance |  | 7,500,000 |  |  |  |

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