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Stockholders' Equity (Narratives) (Details) - USD ($) |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jan. 24, 2020 | Nov. 07, 2019 | Nov. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2019 | Nov. 02, 2018
Class Of Stock [Line Items] |  |  |  |  |  |  |  |
Stock repurchase, authorized amount |  |  |  |  |  |  |  | $ 60,000,000.0
Maximum amount of common stock may be repurchased in calendar year |  |  |  |  |  |  | $ 35,000,000.0 |
Payment for intial delivery of shares |  |  |  |  | $ 25,179,000 | $ 15,000,000 |  |
Equity forward contract |  |  |  | $ (4,821,000) | $ (4,821,000) |  |  |
Accelerated Share Repurchase Agreement "November 2019" |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |
Payment for intial delivery of shares |  |  | $ 30,000,000.0 |  |  |  |  |
Initial delivery of shares repurchased |  |  | 3,850,000 |  |  |  |  |
Value of initial share delivery repurchased |  |  | $ 25,200,000 |  |  |  |  |
Equity forward contract |  |  | $ 4,800,000 |  |  |  |  |
Forward contract settlement date |  |  | Jan. 24, 2020 |  |  |  |  |
Additional shares of common stock received | 381,505 |  |  |  |  |  |  |
2013 Equity Incentive Plan |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |
Increase in authorized shares for issuance |  | 7,000,000 |  |  |  |  |  |

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