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Stockholders' Equity (Details) - USD ($) | 3 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2019 | Dec. 04, 2019 | May 02, 2019 | Feb. 06, 2019 | Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Common Stock, Shares Authorized | 100,000,000 |  | 100,000,000 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted | 49,579 |  |  |  |  |  |
Shares, Issued |  |  |  | 39,767 |  | 264,815 |
Shares Issued, Shares, Share-based Payment Arrangement, Forfeited |  |  | 97,985 |  |  |  |
Shares, vested | 49,678 |  |  |  |  |  |
Shares, Outstanding | 156,919 |  |  |  |  |  |
Common Stock, Capital Shares Reserved for Future Issuance | 752,614 |  |  |  |  |  |
Stock Repurchase Program, Number of Shares Authorized to be Repurchased | 1,500,000 |  |  |  | 1,000,000.0 |  |
Treasury Stock Acquired, Average Cost Per Share | $ 22.51 | $ 16.08 |  |  |  |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation | 17,427 | 85,988 |  |  |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $ 3,687,000 |  |  |  |  |  |
Restricted Stock [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Share-based Payment Arrangement, Expense | 366,000 | $ 0 |  |  |  |  |
Phantom Share Units (PSUs) [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Share-based Payment Arrangement, Expense | 100,000 | $ 42,000 |  |  |  |  |
Performance Based Phantom Shares [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Share-based Payment Arrangement, Expense | $ 429,000 |  |  |  |  |  |
Treasury Stock [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Treasury Stock, Shares, Acquired | 37,244 | 132,121 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period | 95,409 |  |  |  |  |  |
Shares, Issued | 826,353 | 763,426 | 884,518 |  |  |  | 843,993
Share-based Payment Arrangement, Nonemployee [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period |  | 212,688 |  |  |  |  |
Share Repurchase Program [Domain] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Treasury Stock, Shares, Acquired | 19,817 | 46,133 |  |  |  |  |
Equity Incentive Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Common Stock, Shares Authorized | 3,000,000.0 |  |  |  |  |  |

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