Leases, Codification Topic 842 (Policies)	12 Months Ended
Sep. 30, 2020
Leases [Abstract]
Leases	Leases On October 1, 2019, we adopted new accounting guidance related to the accounting for leases. Under the new guidance, we recognize assets and liabilities on the balance sheet related to the rights and obligations created by lease agreements with terms greater than 12 months, regardless of whether they are classified as finance or operating leases. Accordingly, on the date of adoption, we recognized ROU assets and lease liabilities in “Other assets” and “Other payables,” respectively, on our Consolidated Statement of Financial Condition. We have operating leases for the premises we occupy in many of our U.S. and foreign locations, including our employee-based branch office operations. At inception, we determine if an arrangement to utilize a building or piece of equipment is a lease and, if so, the appropriate lease classification. Substantially all of our leases are operating leases. If the arrangement is determined to be a lease, we recognize an ROU asset and a corresponding lease liability on our Consolidated Statements of Financial Condition. ROU assets represent our right to use an underlying asset for the lease term, and lease liabilities represent our obligation to make lease payments arising from the lease. We elected the practical expedient, where leases with an initial term of 12 months or less are not recorded as an ROU asset or lease liability. Our lease terms include any noncancelable periods and may reflect periods covered by options to extend or terminate when it is reasonably certain that we will exercise those options.We record our lease ROU assets at the amount of the lease liability plus any prepaid rent and initial direct costs, less any lease incentives and accrued rent. We record lease liabilities at commencement date based on the present value of lease payments over the lease term, which is discounted using our commencement date incremental borrowing rate, or at the imputed rate within the lease, as appropriate. Our incremental borrowing rate considers the weighted-average yields on our senior notes payable, adjusted for collateralization and tenor. Payments that vary because of changes in facts or circumstances occurring after the commencement date, such as operating expense payments under a real estate lease, are considered variable and are expensed in the period incurred. For our real estate leases, we elected the practical expedient to account for the lease and non-lease components as a single lease. Lease expense for our lease payments is recognized on a straight-line basis over the lease term if the ROU asset has not been impaired or abandoned. Lease expense is recognized on a straight-line basis over the lease term if the ROU asset has not been impaired or abandoned.Variable lease costs in the preceding table includes payments for common area maintenance charges and other variable costs that are not reflected in the measurement of ROU assets and lease liabilities.

Leases, Codification Topic 842 (Policies)

12 Months Ended

Sep. 30, 2020

On October 1, 2019, we adopted new accounting guidance related to the accounting for leases. Under the new guidance, we recognize assets and liabilities on the balance sheet related to the rights and obligations created by lease agreements with terms greater than 12 months, regardless of whether they are classified as finance or operating leases. Accordingly, on the date of adoption, we recognized ROU assets and lease liabilities in “Other assets” and “Other payables,” respectively, on our Consolidated Statement of Financial Condition.

We have operating leases for the premises we occupy in many of our U.S. and foreign locations, including our employee-based branch office operations. At inception, we determine if an arrangement to utilize a building or piece of equipment is a lease

and, if so, the appropriate lease classification. Substantially all of our leases are operating leases. If the arrangement is determined to be a lease, we recognize an ROU asset and a corresponding lease liability on our Consolidated Statements of Financial Condition. ROU assets represent our right to use an underlying asset for the lease term, and lease liabilities represent our obligation to make lease payments arising from the lease. We elected the practical expedient, where leases with an initial term of 12 months or less are not recorded as an ROU asset or lease liability. Our lease terms include any noncancelable periods and may reflect periods covered by options to extend or terminate when it is reasonably certain that we will exercise those options.We record our lease ROU assets at the amount of the lease liability plus any prepaid rent and initial direct costs, less any lease incentives and accrued rent. We record lease liabilities at commencement date based on the present value of lease payments over the lease term, which is discounted using our commencement date incremental borrowing rate, or at the imputed rate within the lease, as appropriate. Our incremental borrowing rate considers the weighted-average yields on our senior notes payable, adjusted for collateralization and tenor. Payments that vary because of changes in facts or circumstances occurring after the commencement date, such as operating expense payments under a real estate lease, are considered variable and are expensed in the period incurred. For our real estate leases, we elected the practical expedient to account for the lease and non-lease components as a single lease. Lease expense for our lease payments is recognized on a straight-line basis over the lease term if the ROU asset has not been impaired or abandoned. Lease expense is recognized on a straight-line basis over the lease term if the ROU asset has not been impaired or abandoned.Variable lease costs in the preceding table includes payments for common area maintenance charges and other variable costs that are not reflected in the measurement of ROU assets and lease liabilities.