Profit Sharing Plan	9 Months Ended
Jun. 30, 2020
Retirement Benefits [Abstract]
Profit Sharing Plan	Profit Sharing PlanThe Company participates in a multiple employer 401(k) profit sharing plan ("401(k) Plan"). All employees are eligible to participate, beginning with the first day of the month coincident with or immediately following the completion of one year of service and having reached the age of 21. In addition to employee contributions, the Company may contribute discretionary amounts for eligible participants. Contribution rates for participating employees must be equal. The Company contributed $1.8 million and $5.1 million to the 401(k) Plan for the three and nine months ended June 30, 2020, respectively, and $1.5 million and $4.4 million for the three and nine months ended June 30, 2019, respectively.

The entire disclosure of an entity's employee compensation and benefit plans, excluding share-based compensation and 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, 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 712
-URI http://asc.fasb.org/topic&trid=2197446

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-URI http://asc.fasb.org/topic&trid=2235017

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

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