Consolidated Balance Sheets - USD ($) $ in Millions		Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Investments - Available-for-sale, at fair value:
Fixed maturities (amortized cost: $15,520.6, $12,265.4, and $13,374.2)		$ 15,589.0	$ 13,549.2	$ 12,498.6
Equity securities:
Nonredeemable preferred stocks (cost: $632.4, $497.1, and $590.4)		772.3	827.5	760.2
Common equities (cost: $1,351.7, $1,265.2, and $1,289.2)		2,546.8	2,492.3	2,381.7
Short-term investments (amortized cost: $1,669.3, $3,118.7, and $2,149.0)		1,669.3	2,149.0	3,118.7
Total investments at fair value	[1],[2]	20,577.4	19,018.0	18,759.2
Cash		263.8	108.4	126.1
Accrued investment income		100.4	87.3	82.9
Premiums receivable, net of allowance for doubtful accounts of $140.6, $133.4, and $152.2		3,867.3	3,537.5	3,566.3
Reinsurance recoverables, including $46.2, $36.2, and $46.0 on paid losses and loss adjustment expenses		1,402.3	1,231.9	1,135.0
Prepaid reinsurance premiums		233.0	85.3	89.8
Deferred acquisition costs		568.2	457.2	479.0
Property and equipment, net of accumulated depreciation of $770.3, $706.3, and $731.0		1,018.9	960.6	952.5
Goodwill		472.9	1.6	1.6
Intangible assets, net of accumulated amortization of $16.3, $0.6, and $0.6		526.0	11.3	11.3
Other assets		274.0	288.5	249.0
Total assets		29,304.2	25,787.6	25,452.7
Liabilities
Unearned premiums		6,641.9	5,440.1	5,582.6
Loss and loss adjustment expense reserves		9,701.2	8,857.4	8,639.9
Net deferred income taxes		176.0	98.9	98.8
Dividends payable		0.0	404.1	0.0
Accounts payable, accrued expenses, and other liabilities		2,252.9	1,893.8	2,134.2
Debt, Long-term and Short-term, Combined Amount	[3]	2,739.0	2,164.7	2,208.0
Total liabilities		21,511.0	18,859.0	18,663.5
Redeemable noncontrolling interest (NCI)		433.4	0.0	0.0
Common Shares, $1.00 par value (authorized 900.0; issued 797.6, including treasury shares of 211.7, 206.1, and 209.8)		585.9	587.8	591.5
Paid-in capital		1,177.0	1,184.3	1,169.3
Retained earnings		4,694.9	4,133.4	3,989.5
Accumulated other comprehensive income, net of tax:
Net unrealized gains (losses) on securities		907.5	1,021.9	1,035.3
Net unrealized gains (losses) on forecasted transactions		(7.5)	1.5	2.5
Foreign currency translation adjustment		(0.8)	(0.3)	1.1
Accumulated other comprehensive (income) loss attributable to noncontrolling interest		2.8	0.0	0.0
Total accumulated other comprehensive income		902.0	1,023.1	1,038.9
Total shareholders’ equity		7,359.8	6,928.6	6,789.2
Total liabilities, redeemable NCI, and shareholders’ equity		$ 29,304.2	$ 25,787.6	$ 25,452.7

[1] Our portfolio reflects the effect of unsettled security transactions and collateral on open derivative positions; at June 30, 2015, $159.7 million was included in "other liabilities," compared to $235.8 million and $31.3 million at June 30, 2014 and December 31, 2014

[2] The total fair value of the portfolio at June 30, 2015 and 2014, and December 31, 2014 included $0.7 billion, $1.1 billion, and $1.9 billion, respectively, of securities held in a consolidated, non-insurance subsidiary of the holding company, net of any unsettled security transactions.

[3] 1Consists of both short-term and long-term debt. See Note 4 - Debt.See notes to consolidated financial statements.