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Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

+ Details

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ 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 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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Summary of Option Activity (Parenthetical) (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Price Per Share, Option granted,	$ 11.49
Weighted Average Price Per Share, Option exercised	$ 7.50	$ 7.50	$ 7.05
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercised, Lower Range			$ 3.67
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercised, Upper Range			$ 14.99