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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Shareholder Return award Performance Measurement Period

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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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Section S99

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-Name Staff Accounting Bulletin (SAB)

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Amount of dividends expected to be paid to holders of the underlying shares or contracted instruments over the term of the instruments life.

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-Publisher FASB

-Name Accounting Standards Codification

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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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Percentage of vesting of share-based compensation awards.

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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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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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The estimated amount of dividends to be paid to holders of the underlying shares (expected dividends) over the option's term. Dividends are taken into account because payment of dividends to shareholders reduces the fair value of the underlying shares, and option holders generally do not receive dividends.

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

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Stock Based Compensation - Additional Information (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	1 Months Ended	3 Months Ended
	Jan. 31, 2014 Age	Apr. 05, 2015	Mar. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award
Number of service-based stock options granted to executive officers		0.1	0.1
Weighted average grant date fair value of stock options granted to executive officers		$ 4.43	$ 5.49
Stock options term		7 years
Stock based compensation expense related to retirement agreement			$ 6,600,000
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
Minimum years of service for retirement to be eligible for PRSUs	10 years
Restricted stock unit awards granted		0.2	0.1
Weighted average grant date fair value of restricted stock units granted		$ 18.21	$ 22.06
Estimated annual dividend amount per share		$ 0.24
Stock price		$ 18.10	$ 19.16
TSR Performance-Based Restricted Stock Units \| Maximum
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 \| Minimum
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
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted		1.4	1.6
Weighted average grant date fair value of restricted stock units granted		$ 17.14	$ 18.19
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 installments		4 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Stock price		$ 18.10	$ 19.16
Period of stock granted to employees and executive officers vest in equal installments		4 years
Estimated annual dividend amount per share		$ 0.24