Compensation Deferrals in Current Year.

No definition available.

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- Definition

Percentage of minimum number of units awarded and vest.

+ References

No definition available.

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- Definition

Percentage of retainer fees.

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No definition available.

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- Definition

Remaining percentage of minimum number of units awarded and vest.

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options non cash compensation.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options potential vest, maximum.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity Instruments other than options potential vest minimum.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options vested and nonvested number.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options vested number.

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No definition available.

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- Definition

Share-based Compensation, Numbers of Option to be Granted During the Year

+ 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 1

-Subparagraph (b)

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-Topic 718

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-Section S99

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-Subparagraph (SAB TOPIC 14.F)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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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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-Publisher FASB

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB

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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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

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- Definition

Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 20

-Section 55

-Paragraph 24

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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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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- Definition

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).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

+ Details

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

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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.

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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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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(1)

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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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

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Share-based Compensation Plans - 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]
Maximum number of shares of common stock issued	10,500,000
Shares available for grant	5,013,920
Compensation cost for share-based payment arrangements	$ 11,472	$ 8,851	$ 12,102
Related tax benefit recognized in net income	4,163	3,113	4,421
Additional net excess tax benefit realized	12,456	2,682	4,018
Expected life of SARs	4 years	4 years	4 years
Aggregate intrinsic value of options and SARs exercised	13,838	4,193	10,123
Cash received on option exercises	15,781	9,739	21,253
Noncash stock-based compensation associated performance contingent restricted stock units	4,427	2,164	5,354
Compensation deferrals in current Year	984
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation, Numbers of Option to be Granted During the Year	123,413
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to nonvested awards	198
Weighted-average fair value of awards granted	$ 4.56	$ 6.57	$ 8.42
Fair market value of the company's stock to calculate intrinsic value	$ 41.72
Stock Appreciation Rights (SARs) [Member] \| After 2006 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum vesting period	1 year
Expected life of SARs	7 years
Stock Appreciation Rights (SARs) [Member] \| Prior 2006 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of SARs	10 years
Stock Options and SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	852,157
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to nonvested awards	9,160
Weighted-Average Period	20 months
Vesting at end of 4 years, if performance targets are not met	50.00%
Vesting at end of 5 years, if performance targets are not met	50.00%
Total performance contingent restricted stock units vested , Minimum shares	311,913
Total performance contingent restricted stock units, Maximum	935,738
Performance Shares [Member] \| 2013 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total performance contingent restricted stock units vested , Minimum shares	151,045
Total performance contingent restricted stock units, Maximum	453,135
Performance Shares [Member] \| 2012 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total performance contingent restricted stock units vested , Minimum shares	160,868
Total performance contingent restricted stock units, Maximum	482,603
Deferred Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock unit qualified for vesting and vested	28,647,000
Percentage of retainer fees deferred into stock units	50.00%
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum vesting period	5 years
Total unrecognized compensation cost related to nonvested awards	2,781
Weighted-Average Period	21 months
Noncash stock-based compensation associated performance contingent restricted stock units	$ 1,358	$ 869	$ 365
Stock unit qualified for vesting and vested	93,400
Restricted stock units outstanding	221,434
Restricted stock units outstanding vested	75,876
Performance contingent restricted stock units vested, shares	34,925
Nonvested [Member] \| Stock Options and SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	852,157