Stock-Based Compensation - Weighted Average Exercise Price and Remaining Term Information about Significant Option Groups Outstanding (Detail)	12 Months Ended
Dec. 31, 2015 USD ($) $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding \| shares	2,079,129
Weighted Average Remaining Term	8 years 7 months 6 days
Weighted Average Exercise Price	$ 2.90
Aggregate Intrinsic Value \| $	$ 1,800
Vested Options [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding \| shares	399,129
Weighted Average Exercise Price	$ 12.14
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 \| shares	1,815,300
Weighted Average Remaining Term	9 years 6 months
Weighted Average Exercise Price	$ 0.69
Aggregate Intrinsic Value \| $	$ 1,800
Less than $10.00 [Member] \| Vested Options [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding \| shares	135,300
Weighted Average Exercise Price	$ 0.70
$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 \| shares	140,870
Weighted Average Remaining Term	4 years
Weighted Average Exercise Price	$ 11.79
$10.00 - $19.99 [Member] \| Vested Options [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding \| shares	140,870
Weighted Average Exercise Price	$ 11.79
$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 \| shares	106,159
Weighted Average Remaining Term	1 year 1 month 6 days
Weighted Average Exercise Price	$ 23.27
$20.00 - $29.99 [Member] \| Vested Options [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding \| shares	106,159
Weighted Average Exercise Price	$ 23.27
$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 \| shares	16,800
Weighted Average Remaining Term	1 month 6 days
Weighted Average Exercise Price	$ 36.95
$30.00 - $39.99 [Member] \| Vested Options [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding \| shares	16,800
Weighted Average Exercise Price	$ 36.95

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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 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

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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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