Summary of Stock Options Activity and Related Information (Detail)	3 Months Ended
Mar. 31, 2016 $ / shares shares
Options
Beginning balance \| shares	50,000
Granted \| shares	0
Canceled \| shares	0
Exercised \| shares	0
Expired/Forfeited \| shares	0
Ending balance \| shares	50,000
Exercisable at March 31, 2016 \| shares	50,000
Weighted Average Exercise Price
Beginning balance \| $ / shares	$ 17.18
Granted \| $ / shares	0
Canceled \| $ / shares	0
Exercised \| $ / shares	0
Expired/Forfeited \| $ / shares	0
Ending balance \| $ / shares	17.18
Exercisable at March 31, 2016 \| $ / shares	$ 17.18

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.

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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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

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(4)
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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.

+ 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)(iv)(3)
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- Definition

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

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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)(iv)(1)
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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 of the plan that expired.

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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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-Publisher FASB
-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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Summary of Stock Options Activity and Related Information (Detail)	3 Months Ended
	Mar. 31, 2016 $ / shares shares
Options
Beginning balance \| shares	50,000
Granted \| shares	0
Canceled \| shares	0
Exercised \| shares	0
Expired/Forfeited \| shares	0
Ending balance \| shares	50,000
Exercisable at March 31, 2016 \| shares	50,000
Weighted Average Exercise Price
Beginning balance \| $ / shares	$ 17.18
Granted \| $ / shares	0
Canceled \| $ / shares	0
Exercised \| $ / shares	0
Expired/Forfeited \| $ / shares	0
Ending balance \| $ / shares	17.18
Exercisable at March 31, 2016 \| $ / shares	$ 17.18