Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Premises and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 443,837	$ 416,920
Less accumulated depreciation and amortization	(169,822)	(148,925)
Premises and equipment, net	274,015	267,995
Future minimum payments due, 2020	5,838
Future minimum payments due, 2021	5,246
Future minimum payments due, 2022	4,698
Future minimum payments due, 2023	4,302
Future minimum payments due, 2024	3,596
Future minimum payments due, thereafter	10,531
Rental expense	6,455	6,477	$ 5,500
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	117,431	110,251
Buildings
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	165,088	156,803
Leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	22,765	22,887
Furniture, software and equipment
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 138,553	$ 126,979
Minimum \| Buildings
Property, Plant and Equipment [Line Items]
Estimated useful life	25 years
Minimum \| Leasehold improvements
Property, Plant and Equipment [Line Items]
Estimated useful life	7 years
Minimum \| Furniture, software and equipment
Property, Plant and Equipment [Line Items]
Estimated useful life	2 years
Maximum \| Buildings
Property, Plant and Equipment [Line Items]
Estimated useful life	40 years
Maximum \| Leasehold improvements
Property, Plant and Equipment [Line Items]
Estimated useful life	15 years
Maximum \| Furniture, software and equipment
Property, Plant and Equipment [Line Items]
Estimated useful life	10 years