XML 47 R37.htm IDEA: XBRL DOCUMENT
v3.25.1

Note 11 - Stock-based Compensation (Tables) | 6 Months Ended
--- | ---
Mar. 31, 2025
Notes Tables |
Share-Based Payment Arrangement, Cost by Plan [Table Text Block] |
​ |  | Three Months Ended March 31, |  |  | Six Months Ended March 31, |
​ |  | 2025 |  |  | 2024 |  |  | 2025 |  |  | 2024 |
Restricted stock units |  | $ | 7,820 |  |  | $ | 5,092 |  |  | $ | 12,435 |  |  | $ | 7,741 |
Employee stock purchase plan |  |  | 211 |  |  |  | 318 |  |  |  | 469 |  |  |  | 670 |
Total stock-based compensation expense |  | $ | 8,031 |  |  | $ | 5,410 |  |  | $ | 12,904 |  |  | $ | 8,411 |
Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] |
​ |  | ​ |  |  | Weighted |
​ |  | ​ |  |  | Average |
​ |  | ​ |  |  | Grant-Date |
​ |  | Shares |  |  | Fair Value |
Outstanding as of September 30, 2024 |  |  | 764,111 |  |  | $ | 59.65 |
Granted |  |  | 558,839 |  |  | $ | 47.50 |
Vested |  |  | (171,507 | ) |  | $ | 60.03 |
Forfeited |  |  | (92,961 | ) |  | $ | 81.65 |
Outstanding as of March 31, 2025 |  |  | 1,058,482 |  |  | $ | 51.05 |
​ |  | Six Months Ended March 31, |
​ |  | 2025 |  |  | 2024 |
Time-based restricted stock units |  |  | 403,150 |  |  |  | 220,174 |
Performance-based restricted stock units |  |  | 155,689 |  |  |  | 388,532 |
Total units |  |  | 558,839 |  |  |  | 608,706 |

X
- Definition Tabular disclosure of cost recognized for award under share-based payment arrangement by plan. Includes, but is not limited to, related tax benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
Name: | us-gaap_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
Name: | us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_TableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration