STOCK COMPENSATION, PLANS (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Number of options
Options outstanding beginning of year (in shares)	6,296,709	6,595,136	6,378,584
Options granted (in shares)	1,987,952	1,443,810	600,000
Options exercised (in shares)	(2,156,898)	(1,552,742)	(47,600)
Options forfeited/cancelled (in shares)	(304,227)	(189,495)	(335,848)
Options outstanding end of year (in shares)	5,823,536	6,296,709	6,595,136
Options vested and exercisable end of year (in shares)	2,555,245
Options expected to vest (in shares)	3,010,762
Weighted-Average Exercise Price
Options outstanding beginning of year (in dollars per share)	$ 7.51	$ 4.65	$ 3.79
Options granted (in dollars per share)	$ 23.60	$ 16.80	$ 14.00
Options exercised (in dollars per share)	$ 4.31	$ 3.53	$ 1.52
Options forfeited/cancelled (in dollars per share)	$ 11.50	$ 11.35	$ 5.30
Options outstanding at end of year (in dollars per share)	$ 13.99	$ 7.51	$ 4.65
Options vested and exercisable end of year (in dollars per share)	$ 5.89
Options expected to vest (in dollars per share)	$ 20.19
Aggregate Intrinsic Value
Options outstanding at beginning of year	$ 66,682	$ 48,447	$ 19,708
Options granted	22,543	1,877	1,200
Options exercised	(66,066)	(22,623)	(499)
Options forfeited/cancelled	(7,131)	(1,279)	(2,250)
Options outstanding at end of year	122,003	66,682	48,447
Options vested and exercisable at end of year	74,230
Options expected to vest	$ 44,409
Unvested restricted stock Number of shares
Unvested at beginning of year (in shares)	659,872	0	0
Granted (in shares)	15,524	757,272	0
Vested (in shares)	(330,468)	(97,400)	0
Unvested at end of year (in shares)	344,928	659,872	0
Unvested restricted stock weighted-average grant date fair value
Unvested at beginning of year (in dollars per share)	$ 17.92	$ 0	$ 0
Granted (in dollars per share)	$ 23.69	$ 17.15	$ 0
Vested (in dollars per share)	$ 17.33	$ 12.00	$ 0
Unvested at end of year (in dollars per share)	$ 18.74	$ 17.92	$ 0

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Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period Total Intrinsic Value

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Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Intrinsic Value

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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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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.

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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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.

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

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including 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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The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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

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