Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenues
Premiums	$ 1,145.5	$ 1,205.8	$ 2,296.8	$ 2,416.8
Net investment income	69.1	70.7	137.4	140.8
Net realized investment gains (losses):
Net realized gains from sales and other	4.3	14.5	26.7	26.6
Net other-than-temporary impairment losses on investments recognized in earnings	(5.0)	(1.9)	(25.9)	(4.6)
Total net realized investment (losses) gains	(0.7)	12.6	0.8	22.0
Fees and other income	8.1	8.0	14.6	16.2
Total revenues	1,222.0	1,297.1	2,449.6	2,595.8
Losses and expenses
Losses and loss adjustment expenses	729.7	744.9	1,429.3	1,518.0
Amortization of deferred acquisition costs	254.4	262.0	513.5	522.6
Interest expense	15.6	15.0	30.3	31.1
Gain on disposal of U.K. motor business	(0.4)	(37.7)	(1.2)	(37.7)
Net loss from repayment of debt	86.1	1.8	86.1	18.5
Other operating expenses	143.7	158.5	290.6	313.7
Total losses and expenses	1,229.1	1,144.5	2,348.6	2,366.2
Income (loss) before income taxes	(7.1)	152.6	101.0	229.6
Income tax expense (benefit):
Current	6.5	5.7	39.9	34.9
Deferred	(15.5)	26.0	(18.9)	18.9
Total income tax (benefit) expense	(9.0)	31.7	21.0	53.8
Income from continuing operations	1.9	120.9	80.0	175.8
Net gain (loss) from discontinued operations (net of tax benefit of $1.7 and $0.1 for the three months ended June 30, 2016 and June 30, 2015 and $2.2 and $0.2 for the six months ended June 30, 2016 and June 30, 2015, respectively)	0.1	(0.2)	0.2	(0.2)
Net income	$ 2.0	$ 120.7	$ 80.2	$ 175.6
Basic:
Income from continuing operations	$ 0.04	$ 2.74	$ 1.86	$ 3.98
Net gain (loss) from discontinued operations	0.01	(0.01)	0.01
Net income per share	$ 0.05	$ 2.73	$ 1.87	$ 3.98
Weighted average shares outstanding	43.0	44.2	43.0	44.2
Diluted:
Income from continuing operations	$ 0.04	$ 2.69	$ 1.84	$ 3.90
Net gain (loss) from discontinued operations	0.01	(0.01)
Net income per share	$ 0.05	$ 2.68	$ 1.84	$ 3.90
Weighted average shares outstanding	43.4	45.0	43.5	45.1