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Loans (Narrative) (Details) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 USD ($) contract | Jun. 30, 2018 contract | Jun. 30, 2019 USD ($) contract | Jun. 30, 2018 contract | Dec. 31, 2018 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | contract | 0 | 0 | 1 | 0 |
Loans Receivable [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged | $ 3,250.0 |  | $ 3,250.0 |  | $ 3,220.0
Federal Reserve Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged | $ 85.0 |  | $ 85.0 |  | $ 82.0

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