Investments (Details 13) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commercial mortgage loans
Impaired mortgage loans
Recorded investment in impaired mortgage loans	$ 9.6	$ 25.9
Unpaid principal balance of impaired mortgage loans	11.1	37.1
Related allowance for impaired mortgage loans	2.4	2.4
Average investment in impaired mortgage loans	17.8	26.6	70.6
Interest income recognized on impaired mortgage loans	0.2	0.5	2.8
Brick and mortar
Impaired mortgage loans
Recorded investment in impaired mortgage loans with no related allowance	5.2	21.5
Recorded investment in impaired mortgage loans with related allowance	4.4	4.4
Unpaid principal balance of impaired mortgage loans with no related allowance	6.7	32.7
Unpaid principal balance of impaired mortgage loans with related allowance	4.4	4.4
Related allowance for impaired mortgage loans	2.4	2.4
Average investment in impaired mortgage loans with no related allowance	13.4	22.2	11.4
Average investment in impaired mortgage loans with related allowance	4.4	4.4	59.2
Interest income recognized on impaired mortgage loans with no related allowance		0.2	2.6
Interest income recognized on impaired mortgage loans with related allowance	0.2	0.3	0.2
Residential mortgage loans
Impaired mortgage loans
Recorded investment in impaired mortgage loans	27.1	33.0
Unpaid principal balance of impaired mortgage loans	27.7	32.1
Related allowance for impaired mortgage loans	9.0	10.2
Average investment in impaired mortgage loans	30.1	36.3	33.7
Interest income recognized on impaired mortgage loans	0.8	1.3	1.0
Home equity
Impaired mortgage loans
Recorded investment in impaired mortgage loans with related allowance	16.5	19.5
Unpaid principal balance of impaired mortgage loans with related allowance	17.1	19.7
Related allowance for impaired mortgage loans	8.2	9.2
Average investment in impaired mortgage loans with related allowance	18.0	20.2	17.7
Interest income recognized on impaired mortgage loans with related allowance	0.6	1.1	0.9
First liens
Impaired mortgage loans
Recorded investment in impaired mortgage loans with no related allowance	3.4	4.6
Recorded investment in impaired mortgage loans with related allowance	7.2	8.9
Unpaid principal balance of impaired mortgage loans with no related allowance	3.4	4.6
Unpaid principal balance of impaired mortgage loans with related allowance	7.2	7.8
Related allowance for impaired mortgage loans	0.8	1.0
Average investment in impaired mortgage loans with no related allowance	4.0	7.2	7.0
Average investment in impaired mortgage loans with related allowance	8.1	8.9	9.0
Interest income recognized on impaired mortgage loans with related allowance	$ 0.2	$ 0.2	$ 0.1

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Topic 310

-SubTopic 10

-Section 50

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