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Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended				3 Months Ended		3 Months Ended	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 Maximum [Member]	Mar. 31, 2014 Stock Option Plan 2000 [Member]	Mar. 31, 2014 Equity Incentive Plan 2003 [Member]	Feb. 28, 2003 Equity Incentive Plan 2003 [Member]	Mar. 31, 2014 Equity Incentive Plan 2003 [Member] Maximum [Member]	Dec. 31, 2013 Two Thousand and Thirteen Stock Incentive Plan [Member]	Oct. 31, 2013 Two Thousand and Thirteen Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares				150,297		4,336,731			1,960,168
Stock reserved for future issuance									1,960,168
Percentage of Common stock share outstanding								4.00%
Options granted, maximum term							10 years
Expected life of option term		7 years	6 years 3 months		6 years 3 months
Weighted-average grant-date fair value of options granted	$ 23.13
Intrinsic value of options exercised	$ 2,500,000
Fair value of shares vested	192,166
Unrecognized compensation cost related to non-vested stock-based compensation arrangements	7,600,000
Unrecognized compensation expense recognition period	4 years
Cash received option exercises	$ 68,061

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Common Stock Capital Shares Minimum Increase In Shares Reserved For Future Issuance

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Percentage of shares of company's common stock outstanding for increase in shares reserved for issuance under stock plan.

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Unrecognized cost of unvested share-based compensation awards.

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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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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.

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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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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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).

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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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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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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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