Derivative Instruments (Derivative Assets Offset in The Consolidated Balance Sheets) (Details) - Interest Rate Swap $ in Thousands	Sep. 30, 2018 USD ($)
Customer Counterparties Loan Interest Rate Swap Assets [Member] \| Non-hedging interest rate derivatives:
Offsetting Assets [Line Items]
Gross amounts of recognized assets	$ 668
Net Amounts of Assets presented in the Statement of Financial Position	668
Fair Value of collateral	668
Total Gross amounts not offset in the statement of financial position including applicable netting agreement and fair value of collateral	668
Net Amount	0
Financial Institution Counterparties Loan Interest Rate Swap Asset [Member] \| Non-hedging interest rate derivatives:
Offsetting Assets [Line Items]
Gross amounts of recognized assets	26,389
Net Amounts of Assets presented in the Statement of Financial Position	26,389
Fair Value of collateral	0
Total Gross amounts not offset in the statement of financial position including applicable netting agreement and fair value of collateral	0
Net Amount	26,389
Financial Institution Counterparties Loan Interest Rate Swap Asset [Member] \| Derivatives designated as hedges of fair value:
Offsetting Assets [Line Items]
Gross amounts of recognized assets	131
Net Amounts of Assets presented in the Statement of Financial Position	131
Fair Value of collateral	66
Total Gross amounts not offset in the statement of financial position including applicable netting agreement and fair value of collateral	66
Net Amount	$ 65

Fair value of securities received as collateral against derivative assets.

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