Securities - Additional Information (Details) $ in Millions	Sep. 30, 2018 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Unrealized losses in investment securities portfolio	$ 7.1
Public Deposits, Derivative Positions and Federal Home Loan Bank Advances
Schedule Of Available For Sale Securities [Line Items]
Carrying value of securities	$ 148.7

Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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