Stock-Based Compensation - Additional Information (Details)	3 Months Ended
Mar. 31, 2018 USD ($) Plan $ / shares shares	Mar. 31, 2017 USD ($) shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options granted \| shares		0
Stock-based compensation	$ 59,600	$ 63,400
Unrecognized compensation costs related to non-vested stock options	$ 412,500
Period over which compensation costs related to non-vested stock options recognize	4 years
Tax benefit from recording non-cash expense relates to options granted to employees	$ 0
Number of stock option plans \| Plan	2
2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option plan expiry date	Mar. 31, 2015
General and Administrative Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 59,600	$ 63,400
Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options granted \| shares	15,024
Weighted average exercise price of options granted \| $ / shares	$ 3.15

Number of stock option plan.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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 (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

+ Details

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- Definition

Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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- Definition

Date the equity-based award expires, in CCYY-MM-DD format.

+ 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 (a)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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

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

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

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