Defined Benefit Plan, Amortization of Actuarial Losses, Amortization Period

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- Definition

Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements, Lump-Sum Payout Offer

+ References

No definition available.

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- Definition

The minimum age for an employee to retire to be covered by the continuation of medical benefits under the postretirement benefit plan.

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No definition available.

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- Definition

Multiemployer Plans, Collective-Bargaining Arrangement, Number of Agreements

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- Definition

Multiemployer Plans, Number of Plans

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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- Definition

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

+ References

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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 contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

+ References

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees.

+ References

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from settlement and curtailment.

+ References

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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-Publisher FASB
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- Definition

Amount of cost for defined contribution plan.

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- Definition

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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Pension and Other Postretirement Benefit Plans - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) agreement pension_plan age	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Services completed by employees for eligibility, retiring age \| age	55
Accumulated benefit obligation	$ 1,034.7	$ 973.7
Tax benefit (expense) related to defined benefit plans recognized in other comprehensive income (loss)	$ (1.5)	(7.1)	$ (8.3)
Number of multi-employer pension plans \| pension_plan	2
Number of collective bargaining agreements \| agreement	3
Defined contribution expense	$ 15.0	14.4	13.3
Defined contribution retirement program
Defined Benefit Plan Disclosure [Line Items]
Defined contribution expense	$ 21.3	$ 21.2	19.4
Unionized employees \| Multi-employer plan total contributions
Defined Benefit Plan Disclosure [Line Items]
Concentration risk percentage (more than)	5.00%	5.00%
April 24, 2020
Defined Benefit Plan Disclosure [Line Items]
Number of collective bargaining agreements \| agreement	1
July 3, 2020
Defined Benefit Plan Disclosure [Line Items]
Number of collective bargaining agreements \| agreement	2
Pension
Defined Benefit Plan Disclosure [Line Items]
Pension settlement and curtailment loss	$ 1.7
Pension \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Period for amortizing actuarial losses	5 years
Estimated minimum required contributions to pension plans in next fiscal year	$ 10.0
Pension \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Period for amortizing actuarial losses	31 years
Estimated minimum required contributions to pension plans in next fiscal year	$ 15.0
Pension \| United States
Defined Benefit Plan Disclosure [Line Items]
Lump-Sum Payout settlement payments	0.0	$ 154.9
Lump-Sum Payout settlement charge		34.2
Curtailment gain (loss)	$ 0.0	0.0	0.0
Pension \| United States \| Equity securities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	50.00%
Pension \| United States \| Equity securities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	75.00%
Pension \| United States \| Debt securities, mutual funds \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	15.00%
Pension \| United States \| Debt securities, mutual funds \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	40.00%
Pension \| United States \| Alternative investments \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	0.00%
Pension \| United States \| Alternative investments \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	30.00%
Pension \| United States \| Cash and other \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	0.00%
Pension \| United States \| Cash and other \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	10.00%
Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Lump-Sum Payout settlement payments	$ 0.0	0.0
Curtailment gain (loss)	$ (0.9)	0.0	$ (7.7)
Pension \| Foreign \| Equity securities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	45.00%
Pension \| Foreign \| Equity securities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	65.00%
Pension \| Foreign \| Debt securities, mutual funds \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	25.00%
Pension \| Foreign \| Debt securities, mutual funds \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	45.00%
Pension \| Foreign \| Alternative investments \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	0.00%
Pension \| Foreign \| Alternative investments \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	25.00%
Pension \| Foreign \| Cash and other \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	0.00%
Pension \| Foreign \| Cash and other \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	15.00%
Other Postretirement \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Period for amortizing actuarial losses	3 years
Other Postretirement \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Period for amortizing actuarial losses	17 years
Other Postretirement \| United States
Defined Benefit Plan Disclosure [Line Items]
Lump-Sum Payout settlement payments	$ 0.0	0.0
Other Postretirement \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Lump-Sum Payout settlement payments	$ 0.0	$ 0.0