Net death benefits from life insurance policies, amount.

No definition available.

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- Definition

Pension and other postretirement benefit plans, amounts that will be amortized from aoci in next fiscal year, pre-tax.

+ References

No definition available.

+ Details

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- Definition

Reclassification of level 3 assets to NAV-based assets.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6812-107765

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

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

+ Details

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- Definition

Amount of contributions received and expected to be received by defined benefit plan from 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)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Notice period the entity is required to deliver before it can redeem an investment calculated using net asset value per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investments calculated by per unit, per membership interest, other equity or ownership interest and alternative investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=SL6742756-110258

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Employee Benefit and Retirement Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer discretionary contribution amount		$ 15.6	$ 17.4	$ 16.5
Defined contribution plan, cost recognized		$ 30.2	25.5	$ 14.0
Fair value, investments, entities that calculate net asset value per share, investment redemption, notice period		90 days
Reclassification of level 3 assets to NAV-based assets			42.3
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension and other postretirement benefit plans, amounts that will be amortized from AOCI in next fiscal year, pre-tax	$ 13.9
United States Pension Plan of US Entity [Member] \| Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year	13.0
International [Member] \| Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year	$ 16.0
Equity Securities [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, target plan asset allocations range maximum		25.00%
Equity Securities [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, target plan asset allocations range maximum		40.00%
Fixed Income Investments [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, target plan asset allocations range maximum		20.00%
Fixed Income Investments [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, target plan asset allocations range maximum		40.00%
Cash and Other Investments [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, target plan asset allocations range maximum		25.00%
Cash and Other Investments [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, target plan asset allocations range maximum		45.00%
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net death benefits from life insurance policies, amount		$ 274.0
Cash surrender value of life insurance		123.0	116.0
Defined benefit plan, benefit obligation		$ 127.0	$ 123.0