Derivative Instruments (Derivative Liabilities Offset in The consolidated Balance Sheets) (Details) - Non-hedging interest rate derivatives: - Interest Rate Swap $ in Thousands	Sep. 30, 2018 USD ($)
Customer Counterparties Loan Interest Rate Swap Liabilities [Member]
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	$ 26,163
Derivative liabilities	26,163
Fair Value of collateral	26,163
Total Gross amounts not offset in the statement of financial position including applicable netting agreement and fair value of collateral	26,163
Net Amount	0
Financial Institution Counterparties Loan Interest Rate Swap Liabilities [Member]
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	668
Derivative liabilities	668
Fair Value of collateral	13,256
Total Gross amounts not offset in the statement of financial position including applicable netting agreement and fair value of collateral	13,256
Net Amount	$ 0

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