Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operations:
Net (loss) income	$ (16.7)	$ (136.3)	$ 51.8
Adjustments to reconcile net (loss) income to net cash provided from (used for) operations:
Net realized and unrealized investment (losses) gains	20.9	37.7	(50.1)
Amortization of premium on fixed maturity investments	5.8	16.6	21.1
Amortization of intangible assets	15.8	10.2
Depreciation and other amortization	9.5	8.9	6.7
Share-based compensation	2.0
Revaluation of contingent consideration	(9.6)	(48.8)
Impairment of intangible assets	8.0	5.0
Excess of fair value of acquired net assets over cost			(4.3)
Undistributed equity in earnings of unconsolidated affiliates, after-tax			(6.6)
Other operating items:
Net change in loss and loss adjustment expense reserves	203.7	188.3	18.1
Net change in reinsurance recoverable on paid and unpaid losses	(95.7)	(11.1)	(23.6)
Net change in funds held by ceding companies	(48.0)	(38.9)	(15.1)
Net change in unearned insurance and reinsurance premiums	195.5	55.7	60.8
Net change in ceded reinsurance payable	93.4	22.8	11.5
Net change in ceded unearned insurance and reinsurance premiums	(76.3)	14.4	(1.9)
Net change in insurance and reinsurance premiums receivable	(144.1)	(102.3)	(95.4)
Net change in deferred acquisition costs	(28.4)	(27.0)	(14.2)
Net change in funds held under reinsurance treaties	42.7	5.8	13.0
Net change in current and deferred income taxes, net	18.7	13.3	(12.0)
Net change in other assets and liabilities, net	(89.2)	(50.3)	(6.6)
Net cash provided from (used for) operations	108.0	(36.0)	(46.8)
Cash flows from investing activities:
Net change in short-term investments	(90.1)	(1.0)	(202.7)
Sales of fixed maturities and convertible fixed maturity investments	1,373.1	1,422.4	2,454.7
Maturities, calls, and paydowns of fixed maturity and convertible fixed maturity investments	102.7	292.2	141.8
Sales of common equity securities	353.1	87.6	851.6
Distributions and redemptions of other long-term investments	72.4	40.6	27.9
Sales of consolidated subsidiaries and unconsolidated affiliates, net of cash sold		0.8	173.5
Contributions to other long-term investments	(160.1)	(167.5)	(73.5)
Purchases of common equity securities	(505.7)	(222.3)	(232.7)
Purchases of fixed maturities and convertible fixed maturity investments	(1,321.3)	(1,018.5)	(3,192.3)
Purchases of consolidated subsidiaries, net of cash acquired	(7.9)	(354.5)	27.5
Net change in unsettled investment purchases and sales	(1.2)	(7.9)	38.4
Other, net	(4.9)	(5.9)	4.3
Net cash (used for) provided from investing activities	(189.9)	66.0	18.5
Cash flows from financing activities:
Proceeds from issuance of common shares, net of expenses	61.2
Redemption of common shares from CM Bermuda	(164.0)
Return of capital to CM Bermuda	(1.6)
Capital contribution from former parent	1.4	13.3	89.6
Issuance of debt, net of issuance costs		340.8	392.4
Redemption of SIG Preference Shares		(250.0)
Repayment of debt		(3.8)	(405.6)
Payment of contingent consideration	(4.4)	(30.6)
Change in collateral held on Interest Rate Cap		(1.1)	(0.5)
Cash dividends paid to former parent			(27.0)
Cash dividends paid to non-controlling interests		(14.1)	(18.8)
Other, net		(0.9)	0.8
Net cash (used for) provided from financing activities	(6.6)	53.6	30.9
Effect of exchange rate changes on cash	(9.9)	9.9	(9.4)
Net (decrease) increase in cash during year	(98.4)	93.5	(6.8)
Cash and restricted cash balance at beginning of year	230.6	137.1	143.9
Cash and restricted cash balance at end of year	132.2	230.6	137.1
Supplemental disclosures of cash flow information:
Income taxes paid	19.1	16.7	8.3
Interest paid	30.0	$ 22.0	$ 31.6
Series B preference shares
Cash flows from financing activities:
Proceeds from issuance of Series B preference shares	195.8
Series A redeemable preference shares
Cash flows from financing activities:
Redemption of Series A redeemable preference shares	$ (95.0)