Condensed Consolidated Cash Flows Statements Reconciliation of Cash, Segregated Cash, Cash Equivalents, and Segregated Cash Equivalents - USD ($) $ in Millions	Jun. 30, 2019	Jun. 30, 2018
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	$ 345.0	$ 347.8
Cash segregated under federal and other regulations(1)	721.0	537.2
Securities segregated under federal and other regulations(1)	300.0	0.0
Cash segregated and deposited with or pledged to exchange-clearing organizations and other futures commissions merchants	1,223.8	738.1
Securities segregated and pledged to exchange-clearing organizations(2)	39.2	53.5
Cash, segregated cash, cash equivalents, and segregated cash equivalents at beginning of period	$ 2,628.6	$ 1,676.6

Deposits with and Receivables From Clearing Organizations, Segregated under Commodity Exchange Act Regulation

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Cash deposited in a special reserve account for the exclusive benefit of customers pursuant to the Commodity Exchange Act.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair value of securities deposited in a special reserve account for the exclusive benefit of customers pursuant to the Commodity Exchange Act.

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Fair value of securities 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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