Equity-Based Compensation Expense - Stock-Based Compensation Plans (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Outstanding at beginning of period (Options)	667
Granted (Options)	675
Exercised (Options)	(99)
Forfeited (Options)	(18)
Outstanding at end of period (Options)	1,225
Exercisable at end of period (Options)	177
Outstanding at beginning of period (Weighted Avg. Exercise Price)	$ 740.18
Granted (Weighted Avg. Exercise Price)	$ 1,094.82
Exercised (Weighted Avg. Exercise Price)	$ 657.85
Forfeited (Weighted Avg. Exercise Price)	$ 819.08
Outstanding at end of period (Weighted Avg. Exercise Price)	$ 941.31
Exercisable at end of period (Weighted Avg. Exercise Price)	$ 627.80

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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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

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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

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No definition available.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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No definition available.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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Number of share options (or share units) exercised during the current period.

+ References

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

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-Name Regulation S-X (SX)

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