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Short-term Borrowings - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2018 USD ($)
Federal Funds Purchased |
Short-term Debt [Line Items] |
Maximum maturity days | 90 days
Trading Liabilities |
Short-term Debt [Line Items] |
Maximum holding days | 90 days
Other Short-term Borrowings |
Short-term Debt [Line Items] |
Maximum original maturity period | 1 year
Fixed Income Securities |
Short-term Debt [Line Items] |
Securities pledged to secure other short term borrowings | $ 71.2

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