The make-whole premium paid to bondholders and expensed by the entity for the early payment of debt.

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- Definition

Non-operating Retirement-related Loss

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No definition available.

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- Definition

Operating Revenue

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No definition available.

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- Definition

Reserve Increase for Long-term Care, Before Tax

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No definition available.

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- Definition

Unclaimed Death Benefit Reserve Increase (Decrease) - the before tax increase (decrease) adjustment to reserves for unclaimed death benefits as a result of searching the Death Master File.

+ References

No definition available.

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- Definition

Waiver of premium benefit reserve increase (decrease) - the before tax adjustment increase (decrease) to reserves due to updated assumptions surrounding waiver of premium reserves

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No definition available.

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- Definition

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c),9(a))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27405-111563

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (c)-(e)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Reconciliation of Operating Revenue and Operating Income by Segment to Total Revenue and Income Before Income Tax (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting, Revenue Reconciling Item
Net Realized Investment Gain	$ (17.3)us-gaap_GainLossOnInvestments	$ 1.2us-gaap_GainLossOnInvestments	$ 25.9us-gaap_GainLossOnInvestments	$ 6.3us-gaap_GainLossOnInvestments	$ 9.3us-gaap_GainLossOnInvestments	$ (26.1)us-gaap_GainLossOnInvestments	$ 13.3us-gaap_GainLossOnInvestments	$ 10.3us-gaap_GainLossOnInvestments	$ 16.1us-gaap_GainLossOnInvestments	$ 6.8us-gaap_GainLossOnInvestments	$ 56.2us-gaap_GainLossOnInvestments
Total Revenue	2,635.7us-gaap_Revenues	2,609.4us-gaap_Revenues	2,653.5us-gaap_Revenues	2,611.1us-gaap_Revenues	2,586.2us-gaap_Revenues	2,540.9us-gaap_Revenues	2,601.9us-gaap_Revenues	2,624.8us-gaap_Revenues	10,509.7us-gaap_Revenues	10,353.8us-gaap_Revenues	10,515.4us-gaap_Revenues
Net Realized Investment Gain	(17.3)us-gaap_GainLossOnInvestments	1.2us-gaap_GainLossOnInvestments	25.9us-gaap_GainLossOnInvestments	6.3us-gaap_GainLossOnInvestments	9.3us-gaap_GainLossOnInvestments	(26.1)us-gaap_GainLossOnInvestments	13.3us-gaap_GainLossOnInvestments	10.3us-gaap_GainLossOnInvestments	16.1us-gaap_GainLossOnInvestments	6.8us-gaap_GainLossOnInvestments	56.2us-gaap_GainLossOnInvestments
Reserve Increase for Long-term Care	(698.2)								(698.2)
Unclaimed Death Benefit Reserve Increase (Decrease) Before Taxes					(95.5)					(95.5)
Waiver of Premium Benefit Reserve Increase (Decrease) Before Tax					85.0
Income Before Income Tax	(457.9)	312.1	346.5	326.5	305.8	284.1	311.5	303.8	527.2	1,205.2	1,249.5
Operating Segments
Segment Reporting, Revenue Reconciling Item
Operating Revenue									10,493.6	10,347.0	10,459.2
Net Realized Investment Gain									16.1	6.8	56.2
Total Revenue									10,509.7	10,353.8	10,515.4
Operating Income									1,292.5	1,241.8	1,239.7
Net Realized Investment Gain									16.1	6.8	56.2
Non-operating Retirement-related Loss									(70.0)	(32.9)	(46.4)
Make-whole Premium on Early Repayment of Debt									13.2	0	0
Reserve Increase for Long-term Care									(698.2)	0	0
Waiver of Premium Benefit Reserve Increase (Decrease) Before Tax									0	85.0	0
Income Before Income Tax									527.2	1,205.2	1,249.5
Unum U.S.
Segment Reporting, Revenue Reconciling Item
Unclaimed Death Benefit Reserve Increase (Decrease) Before Taxes										(75.4)
Waiver of Premium Benefit Reserve Increase (Decrease) Before Tax										(85.0)
Unum U.S. \| Operating Segments
Segment Reporting, Revenue Reconciling Item
Operating Revenue									5,672.1	5,575.0	5,533.4
Operating Income									856.3	859.0	847.1
Unclaimed Death Benefit Reserve Increase (Decrease) Before Taxes									0	(75.4)	0
Colonial Life
Segment Reporting, Revenue Reconciling Item
Unclaimed Death Benefit Reserve Increase (Decrease) Before Taxes										(20.1)
Colonial Life \| Operating Segments
Segment Reporting, Revenue Reconciling Item
Operating Revenue									1,420.5	1,377.8	1,333.4
Operating Income									300.2	284.9	274.3
Unclaimed Death Benefit Reserve Increase (Decrease) Before Taxes									$ 0	$ (20.1)	$ 0