Stock-Based Compensation - Weighted Average Exercise Price and Remaining Term Information about Significant Option Groups Outstanding (Detail) (USD $)	12 Months Ended
Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	428,258
Weighted Average Remaining Term	4 years 3 months 18 days
Weighted Average Exercise Price	$ 19.97
Aggregate Intrinsic Value
Less than $10.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Upper Range	$ 10.00
Number Outstanding	4,050
Weighted Average Remaining Term	7 years 3 months 18 days
Weighted Average Exercise Price	$ 7.42
Aggregate Intrinsic Value
$10.00 - $19.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range	$ 10.00
Exercise Price Upper Range	$ 19.99
Number Outstanding	250,949
Weighted Average Remaining Term	5 years 3 months 18 days
Weighted Average Exercise Price	$ 12.65
Aggregate Intrinsic Value
$20.00 - $29.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range	$ 20.00
Exercise Price Upper Range	$ 29.99
Number Outstanding	117,459
Weighted Average Remaining Term	3 years 1 month 6 days
Weighted Average Exercise Price	$ 23.22
Aggregate Intrinsic Value
$30.00 - $39.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range	$ 30.00
Exercise Price Upper Range	$ 39.99
Number Outstanding	19,800
Weighted Average Remaining Term	1 year 10 months 24 days
Weighted Average Exercise Price	$ 36.46
Aggregate Intrinsic Value
$40.00 - $49.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range	$ 40.00
Exercise Price Upper Range	$ 49.99
Number Outstanding	5,500
Weighted Average Remaining Term	1 year 8 months 12 days
Weighted Average Exercise Price	$ 46.51
Aggregate Intrinsic Value
$50.00 - $59.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range	$ 50.00
Exercise Price Upper Range	$ 59.99
Number Outstanding	30,500
Weighted Average Remaining Term	1 year 8 months 12 days
Weighted Average Exercise Price	$ 53.94
Aggregate Intrinsic Value
Vested Options [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	409,792
Weighted Average Exercise Price	$ 20.42
Vested Options [Member] \| Less than $10.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	2,677
Weighted Average Exercise Price	$ 7.45
Vested Options [Member] \| $10.00 - $19.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	233,856
Weighted Average Exercise Price	$ 12.81
Vested Options [Member] \| $20.00 - $29.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	117,459
Weighted Average Exercise Price	$ 23.22
Vested Options [Member] \| $30.00 - $39.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	19,800
Weighted Average Exercise Price	$ 36.46
Vested Options [Member] \| $40.00 - $49.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	5,500
Weighted Average Exercise Price	$ 46.51
Vested Options [Member] \| $50.00 - $59.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	30,500
Weighted Average Exercise Price	$ 53.94

Share based compensation shares authorized under stock option plans exercise price range aggregate Intrinsic value.

No definition available.

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- Details

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ 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 (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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 (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ 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 (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ 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 (e)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

+ Details

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