Condensed Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Operating Activities:
Net Income	$ 58.4	$ 43.6
Adjustments to Reconcile Net Income to Net Cash Provided (Used) by Operating Activities:
Increase in Deferred Policy Acquisition Costs	(1.1)	(3.9)
Amortization of Life Insurance in Force Acquired and Customer Relationships Acquired	2.1	2.0
Equity in Earnings of Equity Method Limited Liability Investments	(8.6)	(6.7)
Distribution of Accumulated Earnings of Equity Method Limited Liability Investments	3.4	0
Amortization of Investment Securities and Depreciation of Investment Real Estate	4.6	4.1
Net Realized Gains on Sales of Investments	(26.9)	(4.9)
Net Impairment Losses Recognized in Earnings	1.9	0.5
Net Gain on Sale of Portfolio of Automobile Loan Receivables	0	(11.3)
Benefit for Loan Losses	0	(2.0)
Depreciation of Property and Equipment	4.2	3.3
Decrease in Receivables	8.7	7.5
Decrease in Insurance Reserves	(15.7)	(13.1)
Increase (Decrease) in Unearned Premiums	(4.1)	2.1
Change in Income Taxes	25.3	16.2
Increase in Accrued Expenses and Other Liabilities	20.7	6.8
Other, Net	8.4	11.4
Net Cash Provided by Operating Activities	81.3	55.6
Investing Activities:
Sales and Maturities of Fixed Maturities	297.5	103.7
Purchases of Fixed Maturities	(307.5)	(136.1)
Sales of Equity Securities	24.9	7.7
Purchases of Equity Securities	(40.7)	(17.4)
Return of Investment of Equity Method Limited Liability Investments	13.1	10.6
Acquisitions of Equity Method Limited Liability Investments	(5.1)	(9.3)
Increase in Short-term Investments	(36.3)	(116.7)
Improvements of Investment Real Estate	(1.0)	(1.1)
Sales of Investment Real Estate	3.8	0
Increase in Other Investments	(2.0)	(1.8)
Acquisition of Software	(6.6)	(8.1)
Disposition of Business, Net of Cash Disposed	3.8	0
Net Proceeds (Payments) from Sale of Portfolio of Automobile Loan Receivables	(0.5)	20.1
Receipts from Automobile Loan Receivables	0	2.0
Other, Net	(3.7)	(0.3)
Net Cash Used by Investing Activities	(60.3)	(146.7)
Financing Activities:
Common Stock Repurchases	(6.5)	(17.9)
Cash Dividends Paid to Shareholders	(14.0)	(14.5)
Excess Tax Benefits from Share-based Awards	0.3	0.5
Other, Net	0.4	0.5
Net Cash Used by Financing Activities	(19.8)	(31.4)
Increase (Decrease) in Cash	1.2	(122.5)
Cash, Beginning of Year	96.3	251.2
Cash, End of Period	$ 97.5	$ 128.7