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Minimum Retirement Age For Eligible Employees Of Postretirement Plans

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Minimum Years Of Service For Eligible Employees Of Postretirement Plans

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Share Based Compensation Arrangement By Share Based Payment Award Vesting Percentage Upon One Year Anniversary Of Date Of Grant

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Shareholder Return Award Performance Measurement Period

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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Stock-Based Compensation - Additional Information (Detail) - $ / shares shares in Millions	1 Months Ended		6 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jun. 30, 2019	Jul. 01, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award
Estimated annual dividend amount per share			$ 0.36	$ 0.36
Stock price	$ 37.95				$ 47.70
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Period of stock granted to employees and executive officers vest in equal annual installments			4 years
Percentage of common stock price paid			100.00%
Stock options term			7 years
Restricted Stock Units \| Employees
Share-based Compensation Arrangement by Share-based Payment Award
Period of stock granted to employees and executive officers vest in equal annual installments			4 years
Restricted Stock Units \| Director
Share-based Compensation Arrangement by Share-based Payment Award
Period of stock granted to employees and executive officers vest in equal annual installments			1 year
Percentage of awards vesting on the first anniversary of grant date			100.00%
TSR Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Total shareholder return performance measurement period		3 years
Minimum age of retirement to be eligible for PRSUs			60 years
Minimum years of service for retirement to be eligible for PRSUs			10 years
Restricted stock unit awards granted			0.1	0.1
Weighted average grant date fair value of restricted stock units granted			$ 51.51	$ 54.85
Stock price	$ 37.95				$ 47.70
TSR Performance-Based Restricted Stock Units \| Measurement Input, Expected Dividend Payment [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Estimated annual dividend amount per share			$ 0.36	$ 0.36
TSR Performance-Based Restricted Stock Units \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of vesting of target shares upon performance achieved	200.00%
TSR Performance-Based Restricted Stock Units \| Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of vesting of target shares upon performance achieved	0.00%
PBIT Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Total shareholder return performance measurement period	3 years
Restricted stock unit awards granted			0.1	0.1
Weighted average grant date fair value of restricted stock units granted			$ 36.88	$ 46.62
PBIT Performance-Based Restricted Stock Units \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of vesting of target shares upon performance achieved		200.00%
PBIT Performance-Based Restricted Stock Units \| Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of vesting of target shares upon performance achieved		0.00%
Service-Based Restricted Stock Units \| Employees
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted			0.7	0.6
Weighted average grant date fair value of restricted stock units granted			$ 36.10
Weighted average grant date fair value of restricted stock units granted				$ 46.38
Service-Based Restricted Stock Units \| Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted				0.1
Weighted average grant date fair value of restricted stock units granted				$ 12.17
Service-Based Restricted Stock Units \| Non Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted			0.1	0.1
Weighted average grant date fair value of restricted stock units granted			$ 48.03	$ 35.81
Service Based Stock Options \| Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award
Weighted average grant date fair value of restricted stock units granted			$ 10.61
Number options granted during the period			0.1