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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vesting Term

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Share Based Compensation Arrangement By Share Based Payment Award Options Annual Vesting Percentage

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Expiration Period

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Vesting Percentage Year Two

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- Definition

Unexercised Options Expiration Period After Termination Of Employment

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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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-Publisher FASB

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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Unrecognized cost of unvested share-based compensation awards.

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- Definition

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

Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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- Definition

Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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

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

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

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No definition available.

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Stock-Based Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 24, 2012	Mar. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares of common stock available for issuance under the 2011 Plan						15,300,000
Common stock conversion ratio for each RSU upon vesting		1
Unrecognized compensation cost, expected period for recognition		2 years
Incentive compensation expense		$ 3.3	$ 1.7	$ 5.5
Taxes paid related to net share settlement of equity awards		8.4	3.6
Option expiration period		10 years
Dividend per-share	$ 0.15	$ 0.51	$ 0.42	$ 0.18
Weighted-average grant-date fair value of options granted		$ 9.51	$ 9.76	$ 0.00
Total fair value of stock options vested		0	0.7	7.5
Total intrinsic value of stock options exercised		82.3	58.0	24.6
Aggregate intrinsic value of stock options outstanding	80.4	80.4	106.8
Aggregate intrinsic value of stock options exercisable	72.5	72.5	103.8
Unrecognized compensation cost related to non-vested share-based compensation arrangements	4.8	4.8	4.2	0.5
For reason other than death or disability
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period following optionees' termination options cease to be exercisable		90 days
Termination for retirement after the age of 65
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period following optionees' termination options cease to be exercisable		3 years
Termination Due To Death
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period following optionees' termination options cease to be exercisable		12 months
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting percentage on each anniversary of grant date	100.00%	100.00%
Option Vesting period		2 years
Employee Stock Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting percentage on each anniversary of grant date	20.00%	20.00%
Option Vesting period		3 years
Employee Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting percentage on each anniversary of grant date	33.00%	33.00%
Option Vesting period		5 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	3.0	3.0	10.4
Unrecognized compensation cost, expected period for recognition		2 years
Incentive compensation expense		9.8	12.0	0.9
Total fair value of RSUs vested		20.2	9.0		0
Number of shares paying for withholding taxes		300,000	100,000
Taxes paid related to net share settlement of equity awards		8.4	3.6
Restricted Stock Units (RSUs) \| Vesting Schedule One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting term		1 year
Restricted Stock Units (RSUs) \| Vesting Schedule Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting term		2 years
Restricted Stock Units (RSUs) \| Vesting Schedule Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting term		3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	3.4	3.4
Unrecognized compensation cost, expected period for recognition		2 years
Incentive compensation expense		$ 1.6
Restricted Stock \| Vesting Schedule One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting term		1 year
Restricted Stock \| Vesting Schedule Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting term		2 years
Restricted Stock \| Vesting Schedule Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting term		3 years