Defined Contribution Employee Benefit Plan	12 Months Ended
Sep. 30, 2020
Retirement Benefits [Abstract]
Defined Contribution Employee Benefit Plan	Defined Contribution Employee Benefit PlanWe sponsor a defined contribution 401(k) plan, under which our employees elect to withhold specified amounts from their wages to contribute to the plan and we have a fiduciary responsibility with respect to the plan. The plan provides for matching a portion of employees’ contributions at management’s discretion. All contributions and matches by us are invested at the direction of the employee in one or more mutual funds or cash. We made matching contributions of approximately $1.0 million for the years ended September 30, 2020, 2019 and 2018.

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
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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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