CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash acquired	$ 90.9
Restricted cash acquired	53.4
Cash restricted	50.0	$ 0.0	$ 0.0	$ 5.8
Sirius Group
Held for sale and discontinued operations cash balance	$ 0.0	$ 0.0	$ 70.5	$ 245.4

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. 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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Balance Type:	debit
Period Type:	instant