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

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ 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=64937038&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=65897934&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6749337

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6520858

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ 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)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&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)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&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=65897934&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=65897934&loc=d3e1928-114920

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- Details

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Employee Retirement Plans (Details 5) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	100.00%
Fair Value Measurement	$ 442.5	$ 422.8	$ 434.5
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	5.9	1.8
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	436.6	421.0
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	$ 0.0	0.0
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	1.00%
Fair Value Measurement	$ 5.9	1.8
Cash and cash equivalents \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	5.9	1.8
Cash and cash equivalents \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0.0	0.0
Cash and cash equivalents \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	$ 0.0	0.0
Liability hedging portfolio
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	50.00%
Actual Allocation	46.00%
Growth portfolio
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	50.00%
Actual Allocation	53.00%
Debt common trust funds
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	$ 277.2	273.9
Debt common trust funds \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0.0	0.0
Debt common trust funds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	277.2	273.9
Debt common trust funds \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0.0	0.0
Equity common trust funds
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	159.4	147.1
Equity common trust funds \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0.0	0.0
Equity common trust funds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	159.4	147.1
Equity common trust funds \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	$ 0.0	$ 0.0