Benefit Plans - Summary of Activity in Plans (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Compensation And Retirement Disclosure [Abstract]
Shares, Outstanding at beginning of year	948,690
Shares, Granted	7,124
Shares, Exercised	(85,000)
Shares, Forfeited	(290,909)
Shares, Outstanding at end of period	579,905
Shares, Options exercisable at end of period	562,994
Weighted average exercise price, Outstanding at beginning of year	$ 5.44
Weighted average exercise price, Granted	$ 4.11
Weighted average exercise price, Exercised	$ 2.02
Weighted average exercise price, Forfeited	$ 12.24
Weighted average exercise price, Outstanding at end of period	$ 2.52
Weighted average exercise price, Options exercisable at the end of period	$ 2.48
Aggregate intrinsic value, Outstanding at end of period	$ 1,692
Aggregate intrinsic value, Options exercisable at the end of period	$ 1,666

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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)

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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.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)

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

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No definition available.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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

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

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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

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Number of share options (or share units) exercised during the current period.

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-Name Regulation S-X (SX)

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