The number of shares issued cumulatively under the employee stock purchase plan.

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The maximum annual compensation amount to be earned by non-employee directors. Includes grants of share-based compensation awards and any cash fees paid to such non-employee director during the fiscal year.

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Expected vesting date of RSUs granted in connection with the Company's Corporate Incentive Compensation Plan in the current period.

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RSUs granted in connection with the election by employees to receive 50% of their 2015 target incentive compensation in the form of RSUs.

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Closing price of the Company's stock on the last day of the most recent fiscal year end used to compute the aggregate intrinsic value of options outstanding and exercisable or RSUs outstanding and expected to vest as of period end.

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Percentage of an employee's annual target incentive compensation which is eligible to be elected and received in the form of RSUs in accordance with the Company's CICP.

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The total vest date fair value of awards vested during the period.

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Number of options, including both vested and non-vested, and RSUs outstanding as of the balance sheet date.

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The minimum discounted purchase price calculated as a percentage of fair market value of the Company's stock on either the commencement date or completion date of the offerings, whichever is less, at which employees are able to purchase shares under the plan.

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No definition available.

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The current discounted purchase price calculated as a percentage of the fair market value of Company's stock the completion date of the offerings at which employees are able to purchase shares under the plan as determined by the board of directors.

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The dollar value of common stock granted to non-employee directors in consideration of their annual board service in each period.

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No definition available.

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Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
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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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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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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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.

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No definition available.

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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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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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Percentage of vesting of share-based compensation awards.

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

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No definition available.

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Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Gross value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Stock-Based Compensation - Additional Information (Detail)		12 Months Ended
	May 18, 2016	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares	Dec. 31, 2014 USD ($) $ / shares	Jun. 30, 2016 USD ($) shares	Jul. 31, 2011 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option term		10 years
Stock-based compensation arrangement vesting period, in years		5 years
Shares remaining for issuance for future equity grants		10,230,000
2006 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized		1,000,000
Stock price percentage of fair market value		85.00%
Stock purchase price percentage on completion date of offering period		95.00%
Aggregate number of shares issued under plan		351,000
Shares remaining for issuance for future equity grants		649,000
Corporate Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of common stock closing price determine RSU grants for employees		85.00%
2004 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of common stock grantable to non-employee directors \| $		$ 20,000	$ 119,000	$ 95,000
Number of shares authorized					30,000,000
Number of shares outstanding		10,597,000
Shares remaining for issuance for future equity grants		9,581,000
2004 Long-Term Incentive Plan \| As Reported
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized						24,000,000
Common stock split, conversion ratio				2
Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued		1,154,000
Non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued		27,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value of options granted, per share \| $ / shares		$ 8.31	$ 7.62	$ 7.58
Aggregate intrinsic value of options exercised \| $		$ 19,900,000	$ 18,600,000	$ 13,200,000
Closing price of common stock \| $ / shares		$ 36.00
Unrecognized stock-based compensation expense \| $		$ 14,500,000
Weighted-average period of recognition of unrecognized stock-based compensation expense (in years)		2 years 2 months 12 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted		1,929,000
Closing price of common stock \| $ / shares		$ 36.00
Unrecognized stock-based compensation expense \| $		$ 27,800,000
Weighted-average period of recognition of unrecognized stock-based compensation expense (in years)		2 years 1 month 6 days
Weighted-average grant-date fair value of stock units granted \| $ / shares		$ 25.54	$ 20.49	$ 19.88
Stock units, period of vesting		5 years
RSUs granted in connection with the 2016 CICP		225,000
Restricted stock units, fair value \| $		$ 29,200,000	$ 14,900,000	$ 8,000,000
RSUs \| Vesting one year from the grant date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of stock units		20.00%
RSUs \| Vesting quarterly thereafter
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of stock units		80.00%
RSUs \| Corporate Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation percentage of target incentive compensation eligible to be elected and received by employees		50.00%
RSU expected vesting date		2017-03
RSUs \| Corporate Incentive Compensation Plan \| Vesting in March 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of stock units		100.00%
RSUs \| Non-employee directors \| 2004 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted		36,000
Value of RSUs granted to non-employee directors \| $		$ 961,000
RSUs \| Non-employee directors \| 2004 Long-Term Incentive Plan \| Vesting quarterly thereafter
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of stock units	25.00%
RSUs \| Non-employee directors \| 2004 Long-Term Incentive Plan \| Vesting on the date of the annual meeting of stockholders
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of stock units	25.00%
RSUs \| Non-employee directors \| 2004 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of annual common stock grantable to non-employee directors \| $					$ 500,000