Equity - Non-Option Incentive (Details)	12 Months Ended
Dec. 31, 2018 USD ($) employee director $ / shares shares	Dec. 31, 2017 USD ($) employee director $ / shares shares
Weighted Average Grant Date Fair Value Per Share - Non-option
Compensation expense \| $	$ 226,000	$ 296,000
Equity Plan \| Restricted Stock
Number of Shares - Non-option
Outstanding at beginning of year (in shares)	203,334	100,000
Granted during the year (in shares)	280,000	200,000
Restrictions lifted during the year (in shares)	(143,333)	(96,666)
Outstanding at end of year (in shares)	340,001	203,334
Weighted Average Grant Date Fair Value Per Share - Non-option
Outstanding at beginning of year (in dollars per share) \| $ / shares	$ 0.55	$ 0.63
Granted during the year (in dollars per share) \| $ / shares	0.37	0.53
Restrictions lifted during the year (in dollars per share) \| $ / shares	0.44	0.60
Outstanding at end of year (in dollars per share) \| $ / shares	$ 0.45	$ 0.55
Compensation expense \| $	$ 100,000	$ 100,000
Additional compensation expense expected to be recognized \| $	$ 100,000
Period for future recognition of additional compensation expense	24 months	3 years
Restrictions lifted during the year (in shares)	143,333	96,666
Equity Plan \| Restricted Stock \| Employees
Number of Shares - Non-option
Granted during the year (in shares)	280,000	200,000
Weighted Average Grant Date Fair Value Per Share - Non-option
Number of employees \| employee	6
Equity Plan \| Restricted Stock \| Officer
Weighted Average Grant Date Fair Value Per Share - Non-option
Number of employees \| employee		2
Deferred Compensation Plan \| Restricted Stock Units (RSUs)
Number of Shares - Non-option
Outstanding at beginning of year (in shares)	1,887,317	1,607,317
Granted during the year (in shares)	600,000	280,000
Restrictions lifted during the year (in shares)	(257,279)
Outstanding at end of year (in shares)	2,230,038	1,887,317
Weighted Average Grant Date Fair Value Per Share - Non-option
Outstanding at beginning of year (in dollars per share) \| $ / shares	$ 1.16	$ 1.28
Granted during the year (in dollars per share) \| $ / shares	0.42	0.48
Restrictions lifted during the year (in dollars per share) \| $ / shares	1.44
Outstanding at end of year (in dollars per share) \| $ / shares	$ 0.93	$ 1.16
Compensation expense \| $	$ 200,000	$ 100,000
Additional compensation expense expected to be recognized \| $	$ 100,000	$ 40,000
Period for future recognition of additional compensation expense	6 months
Number of board members \| director	6	7
Restrictions lifted during the year (in shares)	257,279
Deferred Compensation Plan \| Restricted Stock Units (RSUs) \| Maximum
Weighted Average Grant Date Fair Value Per Share - Non-option
Additional compensation expense expected to be recognized \| $	$ 100,000
Deferred Compensation Plan \| Restricted Stock Units (RSUs) \| Employees
Number of Shares - Non-option
Restrictions lifted during the year (in shares)	(50,000)	(46,666)
Weighted Average Grant Date Fair Value Per Share - Non-option
Number of employees \| employee		3
Restrictions lifted during the year (in shares)	50,000	46,666
KELTIP \| KELTIP Units
Number of Shares - Non-option
Granted during the year (in shares)	1,620,000	1,020,000
Weighted Average Grant Date Fair Value Per Share - Non-option
Compensation expense \| $	$ 300,000	$ 100,000
KELTIP \| KELTIP Units \| Officers
Number of Shares - Non-option
Granted during the year (in shares)	600,000	435,000
Weighted Average Grant Date Fair Value Per Share - Non-option
Compensation expense \| $	$ 300,000	$ 200,000
Number of employees \| employee	2	2
Vesting immediately \| Equity Plan \| Restricted Stock \| Employees
Number of Shares - Non-option
Granted during the year (in shares)		50,000
Weighted Average Grant Date Fair Value Per Share - Non-option
Percentage of awards which will vest on each of the first, second and third anniversaries of the grant date	33.33%	33.33%
Vest on first anniversary \| Equity Plan \| Restricted Stock \| Employees
Weighted Average Grant Date Fair Value Per Share - Non-option
Percentage of awards which will vest on each of the first, second and third anniversaries of the grant date	33.33%	33.33%
Vest on second anniversary \| Equity Plan \| Restricted Stock \| Employees
Weighted Average Grant Date Fair Value Per Share - Non-option
Percentage of awards which will vest on each of the first, second and third anniversaries of the grant date	33.34%	33.34%

Represents the number of board members the grant made under the scheme.

No definition available.

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Represents number of employees the grant made under the scheme.

+ References

No definition available.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 1
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Unrecognized cost of unvested share-based compensation awards.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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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No definition available.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Percentage of vesting of share-based compensation awards.

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-Name Accounting Standards Codification
-Topic 718
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