Excess Tax Benefit Tax Deficiency From Share Based Compensation Operating Activities

No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
-Article 5

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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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

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

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.

+ References

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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

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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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.

+ References

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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

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.

+ References

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- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

+ References

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Stock Incentive Plans and Stock Based Compensation - Additional Information (Detail)				12 Months Ended
	Jul. 06, 2015	Jan. 29, 2015	Jan. 08, 2014	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares	Dec. 31, 2013 USD ($) $ / shares	Dec. 31, 2015 £ / shares	Dec. 31, 2014 £ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value \| £ / shares							£ 0.50	£ 0.50
Weighted average fair value of the stock options granted \| $ / shares				$ 2.16	$ 1.58	$ 6.18
Cash received from the exercise of options				$ 31,000	$ 307,000	$ 627,000
Intrinsic value of options exercised				6,000	200,000
Unrecognized stock-based compensation expense related to unvested stock option				$ 14,100,000	9,400,000
Unrecognized stock-based compensation expense related to unvested stock option, recognition period				3 years
Excess tax (benefit from) provision on from stock-based awards				$ (727,000)	2,299,000	361,000
Compensation expense related to stock option				7,900,000	7,700,000	14,300,000
Compensation expense in relation to restricted stock units				$ 6,000,000	$ 1,400,000	$ 400,000
Stock Options Granted Prior to June 30, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, Vesting Period				3 years
Stock Options Granted after June 30, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, Vesting Period				4 years
Stock Incentive Plan 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Newly authorized Shares available for award \| shares				31,500,000
Stock Incentive Plan 2011 \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, Vesting Period	4 years	4 years	4 years	4 years
Expire period				10 years