Reinsurance - Other Resinsurance Activity (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Direct Business and Reinsurance:
Direct premiums	$ 71.1us-gaap_DirectPremiumsWritten	$ 80.9us-gaap_DirectPremiumsWritten	$ 79.2us-gaap_DirectPremiumsWritten
Premiums ceded to non-affiliate reinsurers	(58.7)us-gaap_CededPremiumsWritten	(67.0)us-gaap_CededPremiumsWritten	(70.7)us-gaap_CededPremiumsWritten
Premiums	12.4	13.9	8.5
Direct policy benefits incurred	210.1pnx_DirectPolicyBenefitsIncurred	258.5pnx_DirectPolicyBenefitsIncurred	281.4pnx_DirectPolicyBenefitsIncurred
Policy benefits assumed from non-affiliate reinsureds	0.2pnx_PolicyBenefitsAssumedFromReinsureds	0.2pnx_PolicyBenefitsAssumedFromReinsureds	1.0pnx_PolicyBenefitsAssumedFromReinsureds
Affiliate reinsurers	(8.4)	(18.0)	(13.7)
Non-affiliate reinsurers	(82.9)	(119.5)	(114.7)
Policy benefits ceded to reinsurers	(91.3)pnx_PolicyBenefitsCededToReinsurers	(137.5)pnx_PolicyBenefitsCededToReinsurers	(128.4)pnx_PolicyBenefitsCededToReinsurers
Premiums paid to: Affiliate reinsurers	23.8pnx_PremiumsPaidToAffiliateReinsurers	22.3pnx_PremiumsPaidToAffiliateReinsurers	20.1pnx_PremiumsPaidToAffiliateReinsurers
Premiums paid to: Non-affiliate reinsurers	60.4	47.4	60.3
Premiums paid to reinsurers	84.2pnx_PremiumsPaidToReinsurers	69.7pnx_PremiumsPaidToReinsurers	80.4pnx_PremiumsPaidToReinsurers
Policy benefits	203.2	190.9	234.4
Direct life insurance in-force	54,528.7pnx_DirectLifeInsuranceInForce	58,198.8pnx_DirectLifeInsuranceInForce	62,701.8pnx_DirectLifeInsuranceInForce
Life insurance in-force assumed from reinsureds	87.1	93.2	78.5
Life insurance in-force ceded to: Affiliate reinsurers	(1,495.9)	(1,622.9)	(1,859.3)
Life insurance in-force ceded to: Non-affiliate reinsurers	(39,941.5)	(42,957.9)	(46,950.4)
Life insurance in-force ceded to reinsurers	(41,437.4)	(44,580.8)	(48,809.7)
Life insurance in-force	13,178.4pnx_LifeInsuranceInForce	13,711.2pnx_LifeInsuranceInForce	13,970.6pnx_LifeInsuranceInForce
Percentage of amount assumed to net insurance in-force	0.70%	0.70%	0.60%
Changes in reserves, interest credited to policyholders and withdrawals amount	$ 194.5	$ 86.7	$ 154.9

Changes in reserves, interest credited to policyholders and withdrawals amount.

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- Definition

Policy benefits.

+ References

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- Definition

Direct business and reinsurance in continuing operations Permiums.

+ References

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- Definition

Direct life insurance in force.

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Direct policy benefits incurred.

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- Definition

Life insurance in force.

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No definition available.

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- Definition

Life insurance in force assumed from reinsureds.

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- Definition

Life insurance in force ceded to reinsurers.

+ References

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Percentage of amount assumed to net insurance in force.

+ References

No definition available.

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- Definition

Policy benefits assumed from reinsureds.

+ References

No definition available.

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No definition available.

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No definition available.

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- Definition

Policy benefits ceded to reinsurers.

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- Definition

Premiums paid to reinsurers.

+ References

No definition available.

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- Definition

Amount of written premiums ceded to other entities.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 17

-Article 12

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 605

-Section 50

-Paragraph 1

-Subparagraph (b),(c)(2)

-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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- Definition

Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums written.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 17

-Article 12

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 605

-Section 50

-Paragraph 1

-Subparagraph (b),(c)(1)

-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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