Percentage of outstanding common shares and preferred shares on fully diluted basis.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options additional grants in period.

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No definition available.

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- Definition

Stockholders Equity Note [Line Items]

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No definition available.

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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).

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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

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

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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No definition available.

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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

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Equity - Incentive Equity Awards - Additional Information (Detail) - USD ($) $ in Thousands							1 Months Ended		12 Months Ended
	May 20, 2019	Feb. 01, 2019	Nov. 01, 2018	May 14, 2018	Mar. 12, 2018	Feb. 01, 2018	Oct. 31, 2019	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stockholders Equity Note [Line Items]
Stock options, outstanding									15,619,123	19,263,000
Shares issued, exercise of stock options									5,997,919	8,138,305
Proceeds from exercise of stock options, net of transaction costs									$ 24,478	$ 26,402	$ 638
Restricted Stock Units (RSUs)
Stockholders Equity Note [Line Items]
Restricted stock units, outstanding									6,921,071
Percentage of outstanding shares on a fully diluted basis									2.00%
Stock units, Granted									1,473,000	2,633,000
Restricted Stock Units (RSUs) \| Stock Incentive Plan 2011
Stockholders Equity Note [Line Items]
Stock units, Granted	45,163	757,800		190,034		1,305,575
Stock units, Vesting Period	3 years	3 years		3 years		3 years
Stock units, additional granted	20,000
Restricted Stock Units (RSUs) \| Stock Incentive Plan 2011 \| Vesting Period
Stockholders Equity Note [Line Items]
Stock units, Granted			90,000		970,000
Stock units, Vesting Period					3 years
Restricted Stock Units (RSUs) \| Stock Incentive Plan 2011 \| Vest over a three year period
Stockholders Equity Note [Line Items]
Shares issued, related to the vesting of RSUs									387,715
Treasury shares for settlement of employee tax obligations									139,928
Restricted Stock Units (RSUs) \| Stock Incentive Plan 2011 \| Employees
Stockholders Equity Note [Line Items]
Stock units, Granted		580,000
Stock Options
Stockholders Equity Note [Line Items]
Percentage of outstanding shares on a fully diluted basis									4.00%
Stock units, Vesting Period									4 years
Stock Options \| Stock Incentive Plan 2011
Stockholders Equity Note [Line Items]
Stock options, Granted	58,721	1,193,400		286,536		2,205,075
Stock units, Vesting Period		4 years				4 years			4 years
Performance-Based RSUs
Stockholders Equity Note [Line Items]
Shares issued, related to the vesting of RSUs							2,436,750	2,499,750
Treasury shares for settlement of employee tax obligations							1,069,377	764,819