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Stockholders' Equity (Narratives) (Details) - USD ($) |  |  |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Feb. 05, 2020 | Nov. 07, 2019 | Nov. 08, 2018 | Dec. 31, 2020 | Dec. 31, 2020 | 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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