Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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Retirement and Postretirement Plans (Qualified Plan's Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 139.8	$ 146.0	$ 142.8
Qualified Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 139.4	$ 143.2
Asset allocations (as a percent)	100.00%	100.00%
Qualified Plan [Member] \| Level 1 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 139.4	$ 105.8
Qualified Plan [Member] \| Level 2 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	0.0	37.4
Qualified Plan [Member] \| Level 3 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	0.0	0.0
Qualified Plan [Member] \| Fixed maturity investments
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 132.4	$ 24.2
Asset allocations (as a percent)	95.00%	16.90%
Qualified Plan [Member] \| Fixed maturity investments \| Level 1 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 132.4	$ 0.0
Qualified Plan [Member] \| Fixed maturity investments \| Level 2 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	0.0	24.2
Qualified Plan [Member] \| Fixed maturity investments \| Level 3 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	0.0	0.0
Qualified Plan [Member] \| Common equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 0.0	$ 101.0
Asset allocations (as a percent)	0.00%	70.60%
Qualified Plan [Member] \| Common equity securities \| Level 1 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 0.0	$ 101.0
Qualified Plan [Member] \| Common equity securities \| Level 2 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	0.0	0.0
Qualified Plan [Member] \| Common equity securities \| Level 3 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	0.0	0.0
Qualified Plan [Member] \| Convertible fixed maturity investments
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 0.0	$ 12.8
Asset allocations (as a percent)	0.00%	8.90%
Qualified Plan [Member] \| Convertible fixed maturity investments \| Level 1 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 0.0	$ 0.0
Qualified Plan [Member] \| Convertible fixed maturity investments \| Level 2 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	0.0	12.8
Qualified Plan [Member] \| Convertible fixed maturity investments \| Level 3 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	0.0	0.0
Qualified Plan [Member] \| Cash
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 7.0	$ 5.2
Asset allocations (as a percent)	5.00%	3.60%
Qualified Plan [Member] \| Cash \| Level 1 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 7.0	$ 4.8
Qualified Plan [Member] \| Cash \| Level 2 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	0.0	0.4
Qualified Plan [Member] \| Cash \| Level 3 Inputs
Defined Benefit Plan Disclosure [Line Items]
Fair value	$ 0.0	$ 0.0