The amount of additional expenses in connection with the offering.

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This element refers to number of class of warrant or right issued during the period.

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No definition available.

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Represents class of warrant or right repurchase during the period.

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The option to purchase additional shares of common stock to cover over allotment.

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No definition available.

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Adjustment for noncash service expenses paid for by granting of warrants.

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Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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The cash inflow from the additional capital contribution to the entity.

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The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Number of new stock issued during the period.

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Stockholders' equity - Additional Information (Detail) - USD ($)			1 Months Ended						12 Months Ended
	Dec. 14, 2016	Dec. 08, 2016	Jul. 31, 2016	Jan. 31, 2016	Jun. 11, 2014	Mar. 07, 2011	Mar. 04, 2011	Jul. 07, 2010	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stockholders Equity [Line Items]
Common Stock, Shares, Issued									41,465,820	32,804,617
Common Stock, Par Or Stated Value Per Share									$ 0.01	$ 0.01
Proceeds From Issuance Of Common Stock									$ 51,060,000	$ 460,000	$ 15,925,000
Common Stock
Stockholders Equity [Line Items]
Common Stock, Shares, Issued								2,737,500
Stock Unit
Stockholders Equity [Line Items]
Common Stock, Shares, Issued								2,737,500
2010 Offering
Stockholders Equity [Line Items]
Common Stock, Shares, Issued								1,368,750
Common Stock, Par Or Stated Value Per Share								$ 2.00
Proceeds from Issuance or Sale of Equity, Total								$ 4,900,000
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 2.60			$ 0.60	$ 2.60
Adjustment of Warrants Granted for Services								$ 1,300,000
Class Of Warrant Or Right Repurchase During Period							150,000
Class Of Warrant Or Right Issued Unit During Period			7,498	1,161,252		1,218,750
Underwritten Offering
Stockholders Equity [Line Items]
Common Stock, Shares, Issued		6,428,571
Common Stock, Par Or Stated Value Per Share		$ 0.01
Proceeds From Issuance Of Common Stock	$ 48,400,000
Additional Offering Expenses	3,300,000
Underwriters
Stockholders Equity [Line Items]
Proceeds From Issuance Of Common Stock	$ 51,700,000
Stock Issued During Period, Shares, New Issues		6,428,571			7,392,856
Share Price	$ 7.00
Purchase Of Additional Common Stock		964,285			964,285