Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash Flows From Operating Activities
Net income	$ 267.4	$ 134.7
Adjustments to reconcile net income to net cash provided by operating activities:
Net realized and unrealized investment gains	(3.8)	(21.2)
Net amortization and depreciation	21.0	23.0
Stock-based compensation expense	12.1	11.5
Amortization of defined benefit plan costs	7.3	10.5
Deferred income tax (benefit) expense	5.8	(3.1)
Net loss from repayment of debt	1.9
Change in deferred acquisition costs	(28.0)	(45.0)
Change in premiums receivable, net of reinsurance premiums payable	(134.2)	(96.5)
Change in loss, loss adjustment expense and unearned premium reserves	473.7	917.5
Change in reinsurance recoverable	(88.6)	(337.4)
Change in expenses and taxes payable	(49.7)	(53.9)
Other, net	(18.5)	(7.9)
Net cash provided by operating activities	466.4	532.2
Cash Flows From Investing Activities
Proceeds from disposals and maturities of fixed maturities	871.0	819.7
Proceeds from disposals of equity securities and other investments	77.3	138.2
Purchase of fixed maturities	(1,273.6)	(1,296.9)
Purchase of equity securities and other investments	(127.8)	(139.8)
Capital expenditures	(12.4)	(10.7)
Other investing activities		(9.7)
Net cash used in investing activities	(465.5)	(499.2)
Cash Flows From Financing Activities
Proceeds from exercise of employee stock options	12.7	19.2
Change in cash collateral related to securities lending program	(8.3)	(7.3)
Dividends paid to shareholders	(68.9)	(63.8)
Repurchases of common stock	(44.2)	(37.2)
Other financing activities	(3.2)	(3.0)
Net cash used in financing activities	(123.5)	(92.1)
Repayment of debt	11.6
Effect of exchange rate changes on cash	(2.5)	3.7
Net change in cash and cash equivalents	(125.1)	(55.4)
Net change in cash related to discontinued operations	(54.9)	27.7
Cash and cash equivalents, beginning of period	297.9	147.3
Cash and cash equivalents, end of period	$ 117.9	$ 119.6