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

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=65897934&loc=d3e2709-114920

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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The amount of cash or cash equivalents contributed by the entity to fund its pension plans.

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Pension and Postretirement Benefits - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash contributions, pension plans	$ 71.2	$ 64.1	$ 132.5
Cash contributions, other postretirement benefit plans	5.0	$ 5.4	$ 13.6
Pension Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated cash contributions by the company in 2017	141.0
U.S. Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated cash contributions by the company in 2017	54.4
International Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated cash contributions by the company in 2017	86.6
Other Postretirement Benefit Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated cash contributions by the company in 2017	$ 13.0