Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating Activities:
Net Income	$ 155.3	$ 53.8
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Amortization of Intangible Assets Acquired	8.7	0.3
Equity in Earnings of Equity Method Limited Liability Investments	(3.6)	(7.1)
Distribution of Accumulated Earnings of Equity Method Limited Liability Investments	4.3	1.1
Increase in Value of Equity and Convertible Securities at Fair Value	(64.4)	(0.7)
Amortization of Investment Securities and Depreciation of Investment Real Estate	1.6	2.3
Net Realized Gains on Sales of Investments	(16.1)	(2.6)
Net Impairment Losses Recognized in Earnings	3.6	0.5
Depreciation of Property and Equipment	3.1	5.0
Increase in Receivables	(56.1)	(14.5)
Increase in Deferred Policy Acquisition Costs	(29.2)	(12.7)
Increase in Insurance Reserves	3.8	2.1
Increase in Unearned Premiums	75.2	36.3
Change in Income Taxes	40.1	18.1
Change in Accrued Expenses and Other Liabilities	(42.4)	(13.5)
Other, Net	5.1	5.6
Net Cash Provided by Operating Activities	89.0	74.0
Investing Activities:
Sales, Paydowns and Maturities of Fixed Maturities	402.6	397.8
Purchases of Fixed Maturities	(368.4)	(408.6)
Sales of Equity and Convertible Securities	39.6	32.4
Purchases of Equity and Convertible Securities	(207.6)	(51.1)
Sale of and Return of Investment of Equity Method Limited Liability Investments	7.1	1.6
Acquisitions of Equity Method Limited Liability Investments	(18.6)	(3.5)
Decrease (Increase) in Short-term Investments	(53.3)	47.2
Improvements of Investment Real Estate	(0.4)	(0.7)
Increase (Decrease) in Other Investments	(10.6)	2.1
Acquisition and Development of Software	(9.3)	(22.1)
Other, Net	(0.8)	2.9
Net Cash Used by Investing Activities	(219.7)	(2.0)
Financing Activities:
Dividends and Dividend Equivalents Paid	(16.4)	(12.5)
Proceeds from Advances from FHLB	187.7	10.0
Repayments of Debt, Maturing in More than Three Months	(10.0)	0.0
Cash Exercise of Stock Options	1.3	0.6
Other, Net	0.0	(0.4)
Net Cash Provided (Used) by Financing Activities	162.6	(2.3)
Increase in Cash	31.9	69.7
Cash, Beginning of Year	75.1	45.7
Cash, End of Period	$ 107.0	$ 115.4