Pension and Other Postretirement Benefits - Narrative (Details) $ in Millions	6 Months Ended
Jun. 30, 2016 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions to pension and other postretirement benefit plans in current year	$ 14.3
US Qualified Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to pension plan in current period	$ 5.0

The increase in the fair value of plan assets from contributions made by the employer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of the employer's best estimate of contributions expected to be paid to the plan in the current fiscal period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2709-114920

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