Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012		Sep. 30, 2012
Investments - Available-for-sale, at fair value:
Fixed maturities (amortized cost: $13,644.9, $11,864.0, and $11,373.9)	$ 13,797.7		$ 11,774.1		$ 12,295.2
Equity securities:
Nonredeemable preferred stocks (cost: $442.1, $430.1, and $404.0)	726.0		812.4		848.4
Common equities (cost: $1,422.3, $1,101.5, and $1,370.3)	2,326.1		1,899.0		1,639.2
Short-term investments (amortized cost: $1,146.1, $2,394.1, and $1,990.0)	1,146.1		1,990.0		2,394.1
Total investments	17,995.9	[1],[2]	16,475.5	[1],[2]	17,176.9	[1],[2]
Cash	100.9		179.1		192.2
Accrued investment income	91.5		90.0		88.2
Premiums receivable, net of allowance for doubtful accounts of $133.7, $133.5, and $138.6	3,500.8		3,183.7		3,356.0
Reinsurance recoverables, including $36.4, $32.5, and $38.9 on paid losses and loss adjustment expenses	1,031.9		901.0		880.5
Prepaid reinsurance premiums	82.6		66.3		72.8
Deferred acquisition costs	474.7		434.5		461.8
Net deferred income taxes	27.4		109.4		105.3
Property and equipment, net of accumulated depreciation of $665.8, $603.7, and $625.0	955.3		933.7		918.2
Other assets	247.9		321.5		235.3
Total assets	24,508.9		22,694.7		23,487.2
Liabilities and Shareholders’ Equity
Unearned premiums	5,477.9		4,930.7		5,203.4
Loss and loss adjustment expense reserves	8,310.3		7,838.4		7,760.2
Accounts payable, accrued expenses, and other liabilities	1,917.5		1,855.5		1,906.3
Debt	2,010.6	[3]	2,063.1	[3]	2,062.7	[3]
Total liabilities	17,716.3		16,687.7		16,932.6
Common Shares, $1.00 par value (authorized 900.0; issued 797.6, 797.7, and 797.7, including treasury shares of 197.6, 193.0, and 193.1)	600.0		604.6		604.7
Paid-in capital	1,123.0		1,077.0		1,048.6
Retained earnings	4,198.7		3,454.4		3,996.2
Accumulated other comprehensive income, net of tax:
Net non-credit related OTTI losses, adjusted for valuation changes	0		(0.3)		(0.6)
Other net unrealized gains (losses) on securities	865.4		863.0		897.2
Total net unrealized gains (losses) on securities	865.4		862.7		896.6
Net unrealized gains on forecasted transactions	4.5		6.1		6.4
Foreign currency translation adjustment	1.0		2.2		2.1
Total accumulated other comprehensive income	870.9		871.0		905.1
Total shareholders’ equity	6,792.6		6,007.0		6,554.6
Total liabilities and shareholders’ equity	$ 24,508.9		$ 22,694.7		$ 23,487.2

[1] The total fair value of the portfolio at September 30, 2013 and 2012, and December 31, 2012 included $1.3 billion, $1.6 billion, and $1.4 billion, respectively, of securities held in a consolidated, non-insurance subsidiary of the holding company.

[2] At September 30, 2013, we had $63.7 million of net unsettled security transactions, including collateral on open derivative positions, recognized in other liabilities, compared to $32.4 million and $90.9 million recognized in other assets at September 30, 2012 and December 31, 2012, respectively.

[3] Consists of both short- and long-term debt. See Note 4 - Debt.