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Defined Benefit Plan, Settlements, Number of Former Employees

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Matching Contribution By Employer As Percentage Of Participants Contribution

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Share Based Compensation Arrangement By Share Based Payment Award Number of Shares Vesting After Achievement of Goals

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Share-based compensation arrangement by share-based payment award, other than options, grants in period, weighted average grant date fair value.

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Share-based compensation arrangement by share-based payment award, other than options, vested in period, weighted average grant date fair value.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan.

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- Definition

Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

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- Definition

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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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.

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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.

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- Definition

Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Net number of share options (or share units) granted during the period.

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Employee plans - Additional Information (Detail)	1 Months Ended	12 Months Ended
Employee plans - Additional Information (Detail)	Dec. 31, 2016 USD ($) Employee	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of unissued common stock available for grant under the plans (in shares) \| shares		3,200,000
Age requirement for vesting provision, minimum		55 years
Completion of service period (in years) for stock awards		5 years
Option vesting period (in years)		3 years
Share-based compensation expense		$ 11,200,000	$ 9,500,000	$ 9,400,000
Grants of stock option awards (in shares) \| shares		0
Proceeds from exercise of stock options		$ 0	0	3,700,000
Matching contribution by the company as percentage of participants' contribution		50.00%
Percentage of eligible pay contributed by participants that will be matched		6.00%
Cost recognized for contribution plans		$ 10,800,000	10,700,000	9,900,000
Deferred compensation liability	$ 12,300,000	13,400,000	12,300,000
Number of former associates \| Employee	5,800
Lump sum payments made to former associates	$ 215,900,000
International Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cost recognized for contribution plans		18,500,000	19,000,000	21,400,000
Pension Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected pretax amortization of net loss in 2017		167,600,000
Expected pretax amortization of prior service cost (credit) in 2017		6,300,000
Amortization of net loss		176,200,000
Amortization of prior service credit		(4,900,000)
Estimated cash contributions by the company in 2017		149,700,000
Pension Plans \| U.S. Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Curtailment gain		0	0	0
Amortization of net loss		126,400,000	116,000,000	132,700,000
Amortization of prior service credit		(2,500,000)	(2,500,000)	(2,400,000)
Estimated cash contributions by the company in 2017		86,300,000
Pension Plans \| International Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Curtailment gain		5,400,000	2,000,000	0
Amortization of net loss		49,800,000	40,300,000	63,600,000
Amortization of prior service credit		(2,400,000)	(3,000,000)	(1,900,000)
Estimated cash contributions by the company in 2017		63,400,000
Other Postretirement Benefit Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected pretax amortization of net loss in 2017		1,200,000
Expected pretax amortization of prior service cost (credit) in 2017		(1,600,000)
Amortization of net loss		800,000	500,000	1,800,000
Amortization of prior service credit		(700,000)	0	1,100,000
Estimated cash contributions by the company in 2017		12,000,000
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		10,100,000	7,500,000	4,700,000
Total unrecognized compensation cost		$ 9,800,000
Unrecognized compensation cost, Weighted-average recognition period		1 year 10 months 25 days
Aggregate weighted-average grant-date fair value of units granted		$ 14,400,000	12,900,000	10,200,000
Aggregate weighted-average grant-date fair value of units vested		7,400,000	3,500,000	2,100,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		1,100,000	$ 2,000,000	4,700,000
Total intrinsic value of options exercised		0		$ 600,000
Total unrecognized compensation cost		$ 100,000
Unrecognized compensation cost, Weighted-average recognition period		6 months
Performance-Based Unit \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares which will vest after achievement of goals (in shares) \| shares		0
Performance-Based Unit \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares which will vest after achievement of goals (in shares) \| shares		2
Options Issued in 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum contractual term of options granted (in years)		7 years
Options Issued Before 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum contractual term of options granted (in years)		5 years