Compensation Related Costs Share Based Payments Disclosure [Line Items]

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Period When Stock Options Expire In Years

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Share Based Compensation Arrangement by Share Based Payment Award, Expiration Term

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Maximum number of awards outstanding under the plan that are available for issuance if cancelled/forfeited.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Granted, Fair Value

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Underlying Options, Exercised

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Underlying Options, Value At Grant Date

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The total fair value of shares issued during the period under a deferred compensation arrangement.

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Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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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Unrecognized cost of unvested options awarded to employees as compensation.

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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.

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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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- Definition

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 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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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.

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

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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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Percentage of vesting of share-based compensation awards.

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Weighted average remaining contractual term for fully vested and expected to vest options that are 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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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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STOCK-BASED COMPENSATION, Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands			3 Months Ended	9 Months Ended
	Jan. 11, 2012	May. 31, 2006	Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options granted				2,189,424
Underlying options, in shares			5,015	5,015
Options expected to vest			4,634,538	4,634,538
Restricted Stock
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock options issued (in shares)				100,391
Underlying service-based awards, unvested and outstanding (in shares)			576,830	576,830	633,442
Performance-Based Awards
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Total unrecognized compensation cost related to non-vested share-based compensation awards granted			$ 14,384	$ 14,384
Total unrecognized compensation cost related to non-vested share-based compensation awards granted, period for recognition				1 year 5 months 4 days
Stock options issued (in shares)				14,000
Underlying service-based awards, unvested and outstanding (in shares)			250,940	250,940	371,510
2015 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Common stock shares available for issuance (in shares)			6,669,713	6,669,713
2015 Plan \| Stock Options
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options granted				105,724
Aggregate grant-date fair value of stock options				$ 2,789
Unrecognized compensation cost, net of forfeitures			$ 2,677	$ 2,677
Weighted average remaining contractual term, outstanding				9 years 10 months 7 days
Total unrecognized compensation cost related to non-vested share-based compensation awards granted, period for recognition				2 years 4 months 19 days
Options expected to vest			0	0
Vesting percentage				25.00%
2015 Plan \| Service-Based Awards
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Total unrecognized compensation cost related to non-vested share-based compensation awards granted			$ 836	$ 836
Total unrecognized compensation cost related to non-vested share-based compensation awards granted, period for recognition				1 year 11 months
Underlying service-based awards, unvested and outstanding (in shares)			12,096	12,096
Underlying options, value at grant date				$ 905
2015 Plan \| Restricted Stock Units (RSUs) \| Service Period
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Total unrecognized compensation cost related to non-vested share-based compensation awards granted			$ 1,771	$ 1,771
Total unrecognized compensation cost related to non-vested share-based compensation awards granted, period for recognition				2 years 4 months 13 days
Deferred compensation, shares issued			25,000	25,000
Deferred compensation arrangement, fair value of shares issued				$ 1,853
Vesting percentage				25.00%
2012 Directors Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares authorized for issuance (in shares)	600,000
2012 Directors Plan expiration period	10 years
Common stock shares available for issuance (in shares)			554,070	554,070
2012 Directors Plan \| Restricted Stock
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Total unrecognized compensation cost related to non-vested share-based compensation awards granted			$ 377	$ 377
Non-vested common stock shares issued (in shares)			5,295	5,295
Total unrecognized compensation cost related to non-vested share-based compensation awards granted, period for recognition				1 year 2 months 16 days
2012 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Common stock shares subject to outstanding awards that expire or terminate that are available for awards to be granted (in shares)			6,390,069	6,390,069
2012 Plan \| Stock Options
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options granted				2,083,700
Options issued expiration period	10 years
Aggregate grant-date fair value of stock options				$ 44,394
Unrecognized compensation cost, net of forfeitures			$ 67,998	$ 67,998
Weighted average remaining contractual term, outstanding				8 years 7 months 13 days
Total unrecognized compensation cost related to non-vested share-based compensation awards granted, period for recognition				2 years 2 days
Weighted average remaining contractual term, exercisable				7 years 4 months 29 days
2012 Plan \| Service-Based Awards
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Total unrecognized compensation cost related to non-vested share-based compensation awards granted			$ 11,542	$ 11,542
Total unrecognized compensation cost related to non-vested share-based compensation awards granted, period for recognition				1 year 5 months 3 days
Underlying service-based awards, unvested and outstanding (in shares)			427,293	427,293
Underlying options, value at grant date				$ 16,137
2012 Plan \| Restricted Stock Units (RSUs) \| Performance Targets
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Restricted stock units vesting term				3 years
Deferred compensation, shares issued				14,000
Deferred compensation arrangement, fair value of shares issued				$ 983
2012 Plan \| Restricted Stock Units (RSUs) \| Service Period
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Total unrecognized compensation cost related to non-vested share-based compensation awards granted			$ 4,305	$ 4,305
Total unrecognized compensation cost related to non-vested share-based compensation awards granted, period for recognition				2 years 1 month 25 days
Deferred compensation, shares issued			0	58,000
Deferred compensation arrangement, fair value of shares issued				$ 3,560
Vesting percentage				25.00%
2006 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Common stock shares subject to outstanding awards that expire or terminate that are available for awards to be granted (in shares)			1,275,089	1,275,089
2006 Plan \| Stock Options
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options issued expiration period		10 years
Options expected to vest			0	0
Weighted average remaining contractual term, exercisable				5 years 2 months 9 days