Actual tax benefit realized for the tax deduction from vested share-based awards.

No definition available.

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- Definition

Actual tax benefit realized for the tax deductions from options exercised.

+ References

No definition available.

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- Definition

Excess tax benefit if there was no net operating loss carry forwards.

+ References

No definition available.

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- Definition

Excess tax benefit on option exercises if there was no net operating loss carry forward.

+ References

No definition available.

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- Definition

Excess tax expense benefit due to carryforward loss.

+ References

No definition available.

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- Definition

Percentage of target number of performance-based awards will be earned.

+ References

No definition available.

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- Definition

Period option is available to be exercised.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award options and restricted stock vested in period fair value.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award percentage of target number of shares to be issued.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award target number of shares to be issued.

+ References

No definition available.

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- Definition

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

+ 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 (h)(1)(i)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ 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.

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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 cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph i

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 18

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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

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

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.

+ 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 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.

+ References

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Incentive Plan - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
	Mar. 31, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance		8,350,000
Shares available for grant		1,968,625
Share Based Compensation Expenses		$ 11,400,000	$ 8,000,000	$ 5,700,000
Tax benefit		3,900,000	3,200,000	2,100,000
Unrecognized compensation related to non-vested share-based compensation arrangements		18,800,000
Weighted-average period over which unrecognized compensation cost related to non-vested share-based compensation arrangements is expected to be recognized, in years		1 year 10 months 24 days
Total fair value of share-based awards vested		13,000,000	9,100,000	3,900,000
Actual tax benefit realized for the tax deduction from vested share-based awards				619,000
Excess tax benefit due to carryforward loss		0	0
Excess tax benefit if there was no net operating loss carry forwards		1,500,000	1,400,000
Vesting periods	5 years
Total intrinsic value of options exercised		1,000,000	12,400,000	393,000.0
Cash received from option exercises		940,000	7,709,000	430,000
Actual tax benefit realized for the tax deductions from options exercised		0	0	142,000
Excess tax benefit on option exercises if there was no net operating loss carry forward		174,000	3,700,000
Target number of shares to be issued		190,126
Percentage of target number of performance-based awards will be earned		25.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target number of shares to be issued		0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target number of shares to be issued		150.00%
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options expiration period, (in years)		10 years
Cash received from option exercises		$ 798,000	$ 4,500,000	$ 322,000
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting periods		3 years
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting periods		5 years
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting periods		3 years