| Capital Stock - ATM Agreements - Additional Information (Details) - USD ($) | 1 Months Ended | 3 Months Ended | |
|---|---|---|---|
| Feb. 28, 2017 | Mar. 31, 2017 | Nov. 12, 2015 | |
| Common Stock [Member] | |||
| Class Of Warrant Or Right [Line Items] | |||
| Sale of shares | 1,200,000 | ||
| 2015 ATM Agreement [Member] | |||
| Class Of Warrant Or Right [Line Items] | |||
| Sales commission paid per transaction (in hundredths) | 3.00% | ||
| Maximum amount of shares can be issued | $ 75,000,000 | ||
| Proceeds from issuance of common stock | $ 600,000 | ||
| Offering costs offset against proceeds upon sale of common stock | $ 200,000 | ||
| 2015 ATM Agreement [Member] | Common Stock [Member] | |||
| Class Of Warrant Or Right [Line Items] | |||
| Sale of shares | 110,252 | 
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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. No definition available. 
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- Definition The cash inflow from the additional capital contribution to the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition At market issuance sales agreement maximum value of common stock to be issued. No definition available. 
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- Definition The percentage of sales commission to gross proceeds paid to sales agents for the sale of the Company's common shares. No definition available. 
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- Definition Write-off of capitalized offering cost. No definition available. 
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