Compensation Related Costs Share Based Payments Disclosure [Line Items]

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- Definition

Limit of Shares Issued or To Be Issued Pursuant to Options Granted

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No definition available.

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Options, Grants in Period, Weighted Average Option Price

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Option Price

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award Other Than Options Expected Vesting Period

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ 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 (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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

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

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ 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

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

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option 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)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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-Publisher FASB
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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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No definition available.

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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

+ References

No definition available.

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Share-based Awards - Narrative (Detail) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended	6 Months Ended		12 Months Ended	66 Months Ended
	Feb. 14, 2017	May 11, 2015	Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Jun. 30, 2018
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Limit of shares issued or to be issued pursuant to options granted			1,000,000
Non-cash stock compensation expense not yet recognized			$ 60.2	$ 60.2			$ 60.2
Unrecognized stock-based compensation expense, weighted average period (years)				2 years 6 months 6 days
Restricted Stock Units (RSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Fair value of stock units vested				$ 18.4		$ 16.6
Stock units granted				158,775
Performance Share Unit (PSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Fair value of stock units vested				$ 14.7		$ 15.0
Stock units granted				71,906
PSUs Based on Service and EPS Targets
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock units granted							147,630
PSUs Based on Service and EPS Targets \| Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Cumulative EPS vesting period				2015
PSUs Based on Service and EPS Targets \| Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock units to be granted			103,423	103,423			103,423
Cumulative EPS vesting period				2021
Employee Stock Plan, 2008 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance			6,000,000	6,000,000			6,000,000
Employee Stock Plan, 2008 Plan \| Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Additional number of ordinary shares which have been reserved for issuance	400,000
Percentage of option price for fair value of ordinary share				100.00%
Employee Stock Plan, 2008 Plan \| Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Additional number of ordinary shares which have been reserved for issuance	1,000,000
Employee Stock Plan, 2003 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance			6,000,000	6,000,000			6,000,000
Maximum number of award as percentage of shares outstanding				10.00%
Employee Stock Plan, 2003 Plan \| Individual Employee
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance			400,000	400,000			400,000
Employee Stock Option
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares vesting period				5 years
Shares expiration period				8 years
Weighted average contractual term of options outstanding				5 years 29 days
Weighted average fair value per option				$ 13.2
Exercisable - number of shares			562,223	562,223			562,223
Exercisable - weighted average remaining contractual life				3 years 9 months 18 days
Exercisable - weighted average exercise price			$ 48.81	$ 48.81			$ 48.81
Fully vested total intrinsic value			$ 47.1	$ 47.1			$ 47.1
Intrinsic value of option exercised				$ 18.5	$ 14.0
Employee Stock Option \| Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options outstanding fair value			$ 8.53	$ 8.53			$ 8.53
Employee Stock Option \| Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Weighted average contractual term of options outstanding				8 years
Options outstanding fair value			$ 39.96	$ 39.96			$ 39.96
Restricted Stock Units 2008
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance			1,000,000	1,000,000			1,000,000
Restricted Stock Units 2013
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Additional number of ordinary shares which have been reserved for issuance		2,500,000
Ordinary shares which have been reserved for issuance		4,100,000