Investments (Details 12) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Commercial mortgage loans
Impaired mortgage loans
Recorded investment in impaired mortgage loans	$ 8.9		$ 9.6
Unpaid principal balance of impaired mortgage loans	9.2		11.1
Related allowance for impaired mortgage loans	2.4		2.4
Average investment in impaired mortgage loans	9.3	15.6
Interest income recognized on impaired mortgage loans	0.1	0.1
Brick and mortar
Impaired mortgage loans
Recorded investment in impaired mortgage loans with no related allowance	4.5		5.2
Recorded investment in impaired mortgage loans with related allowance	4.4		4.4
Unpaid principal balance of impaired mortgage loans with no related allowance	4.8		6.7
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	4.9	11.2
Average investment in impaired mortgage loans with related allowance	4.4	4.4
Interest income recognized on impaired mortgage loans with related allowance	0.1	0.1
Residential mortgage loans
Impaired mortgage loans
Recorded investment in impaired mortgage loans	26.0		27.1
Unpaid principal balance of impaired mortgage loans	26.7		27.7
Related allowance for impaired mortgage loans	8.7		9.0
Average investment in impaired mortgage loans	26.6	32.5
Interest income recognized on impaired mortgage loans	0.1	0.2
Home equity
Impaired mortgage loans
Recorded investment in impaired mortgage loans with related allowance	15.8		16.5
Unpaid principal balance of impaired mortgage loans with related allowance	16.6		17.1
Related allowance for impaired mortgage loans	8.0		8.2
Average investment in impaired mortgage loans with related allowance	16.2	19.1
Interest income recognized on impaired mortgage loans with related allowance	0.1	0.2
First liens
Impaired mortgage loans
Recorded investment in impaired mortgage loans with no related allowance	3.4		3.4
Recorded investment in impaired mortgage loans with related allowance	6.8		7.2
Unpaid principal balance of impaired mortgage loans with no related allowance	3.3		3.4
Unpaid principal balance of impaired mortgage loans with related allowance	6.8		7.2
Related allowance for impaired mortgage loans	0.7		0.8
Average investment in impaired mortgage loans with no related allowance	3.4	4.6
Average investment in impaired mortgage loans with related allowance	$ 7.0	$ 8.8

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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

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

-Paragraph 17

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-Topic 310

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