Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investments:
Fixed maturities available-for-sale, at fair value (cost: 2018 - $3,529.1; 2017 - $3,320.6)	$ 3,460.4	$ 3,343.4
Equity securities, at fair value (cost: 2018 - $310.6; 2017 - $338.2)	354.5	487.4
Other investments (cost: 2018 - $482.0; 2017 - $534.1)	489.8	543.6
Short-term investments, at fair value (cost: 2018 - $482.3; 2017 - $368.5)	482.3	368.5
Total investments	4,787.0	4,742.9
Cash	139.2	176.6	$ 86.0
Accrued investment income	27.2	23.5
Premiums receivable	649.9	598.6
Reinsurance recoverables	2,688.3	2,093.3
Goodwill	177.0	161.4
Intangible assets, net of accumulated amortization	93.5	96.8
Current income taxes receivable, net	8.2	1.4
Deferred acquisition costs, net	167.3	160.4
Ceded unearned premiums	457.7	399.5
Other assets	362.9	309.6
Total assets	9,558.2	8,764.0
Liabilities and Shareholders' Equity
Reserves for losses and loss adjustment expenses	4,654.6	4,201.0	3,350.8
Unearned premiums	1,300.9	1,207.7
Accrued underwriting expenses	141.4	115.3
Ceded reinsurance payable, net	970.5	734.0
Funds held	37.2	42.7
Senior unsecured fixed rate notes	139.8	139.6
Other indebtedness	183.4	184.5
Junior subordinated debentures	257.0	256.6
Deferred tax liabilities, net	6.2	31.3
Other liabilities	120.5	31.6
Total liabilities	7,811.5	6,944.3
Commitments and contingencies (Note 17)
Shareholders' equity:
Common shares - $1.00 par, 500,000,000 shares authorized; 45,276,999 and 40,385,309 shares issued at December 31, 2018 and December 31, 2017, respectively	45.3	40.4
Additional paid-in capital	1,372.0	1,129.1
Treasury shares (11,315,889 and 10,785,007 shares at December 31, 2018 and December 31, 2017, respectively)	(455.1)	(423.4)
Retained earnings	862.6	977.0
Accumulated other comprehensive (loss) income, net of taxes	(78.1)	96.6
Total shareholders' equity	1,746.7	1,819.7	$ 1,792.7
Total liabilities and shareholders' equity	$ 9,558.2	$ 8,764.0