Additional Stock Based Compensation That Would Have Been Recorded If Operating Income Targets Had Been Deemed Probable

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- Definition

Allocated Share-based Compensation Expense, Cumulative Adjustment

+ References

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Annual Vesting Percentage

+ References

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

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- Definition

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

+ References

No definition available.

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Stock-Based Compensation (Detail) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
Stock-Based Compensation (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2015
Performance-Based Restricted Stock Units Granted in 2015 [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period					800,000
Performance-Based Options Granted in 2015 [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross					300,000
Performance-Based Restricted Stock Units Granted in 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense, Cumulative Adjustment	$ 4.9
Additional stock-based compensation that would have been recorded if operating income targets had been deemed probable					$ 2.5
Performance Based Restricted Stock Units Granted In 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense, Cumulative Adjustment	$ 5.1		$ 3.8
Performance Based Restricted Stock Units Granted In 2012 & 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense, Cumulative Adjustment				$ 6.6
Performance Based Restricted Stock Units [Member] \| Stock Vesting On February Two Thousand Sixteen [Member] \| Performance-Based Restricted Stock Units Granted in 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Annual Vesting Percentage					33.33%
Performance Based Restricted Stock Units [Member] \| Stock Vesting In February Two Thousand Eighteen [Domain] \| Performance-Based Restricted Stock Units Granted in 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Annual Vesting Percentage					33.33%
Performance Based Restricted Stock Units [Member] \| Stock Vesting In February Two Thousand Nineteen [Domain] \| Performance-Based Restricted Stock Units Granted in 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Annual Vesting Percentage					33.33%
MyFitnessPal [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		289,700