Derivative Instruments (Derivative Assets Offset in The Consolidated Balance Sheets) (Details) - Non-hedging interest rate derivatives: - Interest Rate Swap $ in Thousands	Mar. 31, 2019 USD ($)
Customer Counterparties Loan Interest Rate Swap Assets
Offsetting Assets [Line Items]
Gross amounts of recognized assets	$ 6,475
Net Amounts of Assets presented in the Statement of Financial Position	6,475
Fair Value of collateral	6,475
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	6,475
Derivative Asset, Fair Value, Amount Offset Against Collateral	0
Financial Institution Counterparties Loan Interest Rate Swap Asset
Offsetting Assets [Line Items]
Gross amounts of recognized assets	7,077
Net Amounts of Assets presented in the Statement of Financial Position	7,077
Derivative Asset, Fair Value, Gross Liability	5,645
Fair Value of collateral	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	5,645
Derivative Asset, Fair Value, Amount Offset Against Collateral	$ 1,432

Fair value of securities received as collateral against derivative assets.

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