Cash and Due from Banks - Cash and Due from Banks (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Cash and Cash Equivalents [Abstract]
Reserve in cash on hand or at the Federal Reserve as required by Federal Reserve regulations	$ 106.2	$ 107.0
Total restricted cash balance	38.3	36.5
Cash held in interest-bearing accounts	$ 307.8	$ 324.2

No definition available.

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- Definition

Cash deposited in a special reserve account for the exclusive benefit of customers pursuant to regulations other than SEC Regulations and the Commodity Exchange Act.

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- Definition

For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

+ References

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- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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