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

No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ 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)(iii)

-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 can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

+ Details

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ 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

Reference 2: 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

+ Details

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ 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)

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

+ Details

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- Definition

Weighted average remaining contractual term for option awards outstanding, 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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Share-Based Compensation Plans - Summary of Information about Stock Options Outstanding (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options	38,000	40,000	47,000	71,597
Options Outstanding, Weighted Average Remaining Contractual Life	3 years 8 months 5 days
Options Outstanding, Weighted Average Exercise Price Per Share	$ 26.05	$ 25.44	$ 23.19	$ 21.26
Options Exercisable, Number of Options	38,000
Options Exercisable, Weighted Average Exercise Price Per Share	$ 26.05
Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Per Share	$ 22.07
Options Outstanding, Number of Options	4,000
Options Outstanding, Weighted Average Remaining Contractual Life	4 months 10 days
Options Outstanding, Weighted Average Exercise Price Per Share	$ 22.07
Options Exercisable, Number of Options	4,000
Options Exercisable, Weighted Average Exercise Price Per Share	$ 22.07
Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Per Share	$ 24.15
Options Outstanding, Number of Options	24,000
Options Outstanding, Weighted Average Remaining Contractual Life	5 years 3 months
Options Outstanding, Weighted Average Exercise Price Per Share	$ 24.15
Options Exercisable, Number of Options	24,000
Options Exercisable, Weighted Average Exercise Price Per Share	$ 24.15
Range Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Per Share	$ 28.31
Options Outstanding, Number of Options	4,000
Options Outstanding, Weighted Average Remaining Contractual Life	1 year 1 month 28 days
Options Outstanding, Weighted Average Exercise Price Per Share	$ 28.31
Options Exercisable, Number of Options	4,000
Options Exercisable, Weighted Average Exercise Price Per Share	$ 28.31
Range Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Per Share	$ 34.77
Options Outstanding, Number of Options	6,000
Options Outstanding, Weighted Average Remaining Contractual Life	1 year 3 months 11 days
Options Outstanding, Weighted Average Exercise Price Per Share	$ 34.77
Options Exercisable, Number of Options	6,000
Options Exercisable, Weighted Average Exercise Price Per Share	$ 34.77