Loans (Schedule of Contractually Required Payments on Loans Purchased with Deteriorated Credit Quality) (Details) - Loans Acquired With Deteriorated Credit Quality - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	$ 9,926	$ 0
Commercial and Industrial Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	498	0
Commercial Real Estate Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	8,198	0
Agricultural Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	1,230	0
Home Equity Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	0	0
Consumer Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	0	0
Residential Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	$ 0	$ 0