The highest aggregate value of performance units an employee can be granted under the plan per period.

No definition available.

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The highest dollar amount from their salary that an employee is permitted to utilize with respect to the plan.

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No definition available.

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- Definition

Minimum percentage of common stock price to grant date price of stock options to trigger vesting.

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No definition available.

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The percentage of outstanding stock options expected to vest over the remaining vesting period.

+ References

No definition available.

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Threshold period of specified consecutive trading days within which common stock price to grant date price of options must exceed threshold percentage for a specified number of trading days to vesting, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Number of vesting tranches for share based compensation awards with share-price and service vesting requirements.

+ References

No definition available.

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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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.

+ References

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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- Definition

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.

+ References

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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- Definition

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

+ References

+ Details

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

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- Definition

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).

+ References

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- Definition

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.

+ References

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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Period Type:	duration

- Definition

Percentage of vesting of share-based compensation awards.

+ References

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Data Type:	num:percentItemType
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- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

+ Details

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Stock-Based Compensation Plans - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) Tranche shares	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) Tranche $ / shares shares	Sep. 30, 2015 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under ESPP \| shares			141,484	123,866
Incentive plan, percentage of options expected to vest over the vesting period	93.30%		93.30%
Incentive plan, weighted-average grant date fair value of stock options granted \| $ / shares			$ 5.59	$ 6.49
Incentive plan, total intrinsic value of stock options exercised \| $			$ 6,700,000	$ 12,100,000
Expected dividend yield			0.00%
Dividend paid \| $ / shares			$ 0
Number of tranches \| Tranche	3		3
Stock-based compensation expenses \| $	$ 10,800,000	$ 800,000	$ 33,812,000	10,050,000
Stock-based compensation expenses tax benefits \| $	$ 4,100,000	$ 300,000	$ 12,700,000	$ 3,800,000
Employee Stock Purchase Plan 1999 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance \| shares	4,500,000		4,500,000
Permitted designation for purchase of common stock under ESPP			Participating employees are permitted to designate up to the lesser of $25,000 or 10% of their annual base compensation for the purchase of common stock under the ESPP. Purchases under the ESPP are made one calendar month after the end of each fiscal quarter.
Employee participating annual base compensation designated for purchase of common stock, amount \| $	$ 25,000		$ 25,000
Employee participating annual base compensation designated for purchase of common stock, percent	10.00%		10.00%
Price of common stock purchased under ESPP, percent			85.00%
Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vested grant date fair value \| $ / shares			$ 7.46
Share-based compensation, trading price percentage			133.00%
Consecutive trading days			20 days
Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vested grant date fair value \| $ / shares			$ 7.06
Share-based compensation, trading price percentage			167.00%
Consecutive trading days			20 days
Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vested grant date fair value \| $ / shares			$ 6.50
Share-based compensation, trading price percentage			200.00%
Consecutive trading days			20 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expenses \| $	$ 14,600,000		$ 14,600,000
Unrecognized compensation expenses, weighted-average recognition periods			2 years 1 month 6 days
Restricted share awards (RSAs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation awards, shares vested \| shares			114,219
Shares withheld to pay employees' portion of minimum payroll withholding taxes \| shares			9,062
Unrecognized compensation expenses \| $	2,700,000		$ 2,700,000
Unrecognized compensation expenses, weighted-average recognition periods			1 year 4 months 24 days
Retention RSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation awards, shares vested \| shares			226,526
Shares withheld to pay employees' portion of minimum payroll withholding taxes \| shares			76,421
Unrecognized compensation expenses \| $	2,100,000		$ 2,100,000
Unrecognized compensation expenses, weighted-average recognition periods			4 months 24 days
Retention RSAs [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			1 year 3 months 18 days
Retention RSAs [Member] \| Executive Officers [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year			50.00%
Retention RSAs [Member] \| Executive Officers [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year			50.00%
Retention RSAs [Member] \| Employees other than Named Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			9 months 18 days
Retention RSAs [Member] \| Employees other than Named Executive Officers [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year			50.00%
Retention RSAs [Member] \| Employees other than Named Executive Officers [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year			50.00%
Performance-Based Restricted Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation awards, shares vested \| shares			169,567
Shares withheld to pay employees' portion of minimum payroll withholding taxes \| shares			59,659
Unrecognized compensation expenses \| $	5,500,000		$ 5,500,000
Unrecognized compensation expenses, weighted-average recognition periods			1 year 1 month 6 days
LTIP Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expenses \| $	$ 21,300,000		$ 21,300,000
Unrecognized compensation expenses, weighted-average recognition periods			2 years 2 months 12 days
2016 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance \| shares	8,000,000		8,000,000
2016 Incentive Plan \| Stock options, stock appreciation rights, restricted stock, restricted stock units and other awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares of Common Stock a participant may receive \| shares			3,000,000
2016 Incentive Plan \| Performance shares or Performance units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum aggregate value on the date of grant \| $			$ 9,000,000