Premises and Equipment - Schedule of Premises and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 158,163	$ 157,192
Accumulated depreciation	(39,109)	(36,547)
Premise and equipment, net	119,054	120,645
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	31,601	31,107
Buildings and building improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	101,891	95,778
Furniture and equipment
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	24,522	26,688
Construction in progress
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 149	$ 3,619

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 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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