Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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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Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
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Retirement Plans - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	Apr. 30, 2017	Jun. 30, 2017	Jun. 30, 2016
Retirement Plans
Defined Benefit Plan Disclosure [Line Items]
Net pension plan obligation		$ 211.5
Expected contributions to TRP in current fiscal year		20.6
Contributions to plan	$ 1.7
SERP
Defined Benefit Plan Disclosure [Line Items]
Contributions to plan		3.8	$ 3.3
Accrued Liabilities \| Retirement Plans
Defined Benefit Plan Disclosure [Line Items]
Net pension plan obligation		$ 31.0