Employee Benefits	12 Months Ended
Sep. 30, 2020
Retirement Benefits [Abstract]
Employee Benefits	Employee BenefitsWe have established a defined contribution savings plan for eligible employees under the provisions of U.S. Internal Revenue Code Section 401(k) whereby we contribute 100.0% of the first 3.0% and 50.0% of the next 2.0% of an employee’s cash compensation contributed to the plan up to stated maximums. All employees are eligible to participate in the plan and are entitled, upon termination or retirement, to receive their vested portion of the plan assets. Employees’ contributions and our related matching contributions are fully vested when made. Our plan contributions and expenses for the fiscal years ended September 30, 2020, 2019 and 2018 were $2,603, $2,466 and $2,213, respectively.

The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-URI http://asc.fasb.org/topic&trid=2228938

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 712
-URI http://asc.fasb.org/topic&trid=2197446

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-URI http://asc.fasb.org/topic&trid=2127225

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-URI http://asc.fasb.org/topic&trid=2235017

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