Closing stock price per share.

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Common stock exercise price.

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Maximum percentage of payroll for purchase of stock.

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Percentage of payroll deduction to compensation.

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Share based compensation arrangement by share based payment award maximum amount per employee.

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Share based compensation arrangement by share based payment award, options, exercisable shares in the money.

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No definition available.

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- Definition

Percentage of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period.

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award vesting percentage maximum per quarter.

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Share based compensation arrangement by share based payment award vesting period description.

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- Definition

Stock exercise price as percentage of closing market price.

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- Definition

Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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-SubTopic 10

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Aggregate number of common shares reserved for future issuance.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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-Subparagraph (SX 210.5-02.29)

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- Definition

The maximum number of shares authorized for issuance under the deferred compensation arrangement as of the balance sheet date.

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- Definition

Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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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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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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

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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- Definition

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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- 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).

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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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- 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.

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- Definition

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

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-Name Accounting Standards Codification

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, shares issued	53,363,450	52,748,849
Weighted average remaining contractual life of options exercisable	11 months 12 days
Closing stock price per share	$ 29.92
Number of in-the-money options exercisable	105,873
Tax effect on stock-based compensation	$ 495	$ 1,862	$ 5,019
Capitalization of share based payment costs	471	471
Options granted	0	0	0
Total intrinsic value of options exercised	684	1,228	9,458
Weighted average fair value per share of employee stock purchase rights, granted	$ 5.76	$ 7.24	$ 5.87
Total intrinsic value of options exercised and fair value of shares vested	19,221	16,498	27,199
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from employees as a result of employee stock option exercises	1,869	2,322
Tax effect on stock-based compensation	94	299
Stock Incentive Plan 2004 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance	15,000,000
Shares available for future grant	10,916,285
1997 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description	Options granted to directors generally vested at the earliest of (1) one day prior to the next annual meeting, (2) 13 months from date of grant, or (3) the effective date of an acquisition.
Minimum [Member] \| 1997 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period	1 day
Maximum [Member] \| 1997 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period	13 months
Employee Stock Purchase Plan - Second Amended and Restated [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance	400,000
Percentage of Common Stock through payroll deductions	10.00%
Percentage of closing price of the Common Stock	85.00%
Common Stock, shares issued	33,929	29,954
Shares reserved for future issuance	62,541
Employee Stock Purchase Plan - Second Amended and Restated [Member] \| Offer Terminate [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of closing price of the Common Stock	85.00%
Employee Stock Purchase Plan - Second Amended and Restated [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price	$ 23.96	$ 22.01
Employee Stock Purchase Plan - Second Amended and Restated [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of payroll deduction	21,250
Common stock, exercise price	$ 20.42	$ 22.40
Stock Incentive Plans 2001 and After [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of exercise price fair value option grant in period	100.00%
Stock options granted to employees under plans prior to 2001, vested after one year	25.00%
Stock options granted to employees under plans prior to 2001, vested per quarter thereafter	6.25%
Stock options expired	10 years
RSUs Granted to Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description	Earliest of (1) one day prior to the next annual meeting, (2) 13 months from date of grant, or (3) the effective date of an acquisition.
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted to employees under plans prior to 2001, vested after one year	33.30%	33.30%
Stock options expired	3 years
Weighted average fair value per share of employee stock purchase rights, granted	$ 26.81	$ 29.14	$ 30.27
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period	1 day
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period	13 months
RSUs Granted to Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description	Employees who are at least 60 years old and have a combined years of age plus years of service (as defined) equal to 70 years or more, are expensed immediately.
Employee Stock Purchase Plan - Third Amended and Restated [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance	1,950,000
Percentage of payroll deduction to compensation	Up to 10%
Percentage of Common Stock through payroll deductions	10.00%
Percentage of closing price of the Common Stock	85.00%
Common Stock, shares issued	138,674	141,975
Shares reserved for future issuance	212,074
Employee Stock Purchase Plan - Third Amended and Restated [Member] \| Offer Terminate [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of closing price of the Common Stock	85.00%
Employee Stock Purchase Plan - Third Amended and Restated [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price	$ 23.96	$ 22.01
Employee Stock Purchase Plan - Third Amended and Restated [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of payroll deduction	21,250
Common stock, exercise price	$ 20.42	$ 22.40
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 10,934
Estimated weighted average amortization period	1 year 3 months 29 days