Amount of increase to additional paid-in capital (APIC) from modification of previously awarded KELTIP Unit.

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Represents the number of unrestricted common shares that the Director is entitled to receive for each vested RSU, upon termination from board service.

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Represents the amount of liability related to KELTIP Units.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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).

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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).

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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.

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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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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Percentage of vesting of award under share-based payment arrangement.

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Equity - Non-Option Incentive (Details)		1 Months Ended	12 Months Ended
Equity - Non-Option Incentive (Details)	Feb. 26, 2020 USD ($) employee shares	Sep. 30, 2014 shares	Dec. 31, 2019 USD ($) employee director $ / shares shares	Dec. 31, 2018 USD ($) employee director $ / shares shares
Weighted Average Grant Date Fair Value Per Share - Non-option
Compensation expense \| $			$ 782,000	$ 226,000
Modification of previously awarded KELTIP Units \| $			$ 583,000
Sentient \| 2014 Warrants
Number of Shares - Non-option
Granted during the year (in shares)		4,746,000
KELTIP Units \| Officers
Number of Shares - Non-option
Granted during the year (in shares)	705,000
Weighted Average Grant Date Fair Value Per Share - Non-option
Number of employees \| employee	2
Equity Plan \| Restricted Stock
Number of Shares - Non-option
Outstanding at beginning of year (in shares)			340,001	203,334
Granted during the year (in shares)			312,000	280,000
Restrictions lifted during the year (in shares)			(333,998)	(143,333)
Outstanding at end of year (in shares)			318,003	340,001
Weighted Average Grant Date Fair Value Per Share - Non-option
Outstanding at beginning of year (in dollars per share) \| $ / shares			$ 0.45	$ 0.55
Granted during the year (in dollars per share) \| $ / shares			0.26	0.37
Restrictions lifted during the year (in dollars per share) \| $ / shares			0.41	0.44
Outstanding at end of year (in dollars per share) \| $ / shares			$ 0.30	$ 0.45
Compensation expense \| $			$ 100,000	$ 100,000
Additional compensation expense expected to be recognized \| $			$ 100,000
Period for future recognition of additional compensation expense			18 months
Assumptions noted by using the Black-Scholes option pricing model for estimating fair value of each option award
Restrictions lifted during the year (in shares)			333,998	143,333
Equity Plan \| Restricted Stock \| Employees
Number of Shares - Non-option
Granted during the year (in shares)			312,000	280,000
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)			2,230,038	1,887,317
Granted during the year (in shares)			600,000	600,000
Restrictions lifted during the year (in shares)				(257,279)
Outstanding at end of year (in shares)			2,830,038	2,230,038
Weighted Average Grant Date Fair Value Per Share - Non-option
Outstanding at beginning of year (in dollars per share) \| $ / shares			$ 0.93	$ 1.16
Granted during the year (in dollars per share) \| $ / shares			0.24	0.42
Restrictions lifted during the year (in dollars per share) \| $ / shares				1.44
Outstanding at end of year (in dollars per share) \| $ / shares			$ 0.78	$ 0.93
Compensation expense \| $			$ 200,000
Additional compensation expense expected to be recognized \| $			$ 100,000	$ 100,000
Period for future recognition of additional compensation expense				6 months
Number of unrestricted shares Director to receive for vested RSU upon termination from board			1
Number of board members \| director			6	6
Assumptions noted by using the Black-Scholes option pricing model for estimating fair value of each option award
Restrictions lifted during the year (in shares)				257,279
Deferred Compensation Plan \| Restricted Stock Units (RSUs) \| Employees
Number of Shares - Non-option
Restrictions lifted during the year (in shares)			(229,998)	(50,000)
Weighted Average Grant Date Fair Value Per Share - Non-option
Number of employees \| employee			5
Assumptions noted by using the Black-Scholes option pricing model for estimating fair value of each option award
Restrictions lifted during the year (in shares)			229,998	50,000
KELTIP \| KELTIP Units
Number of Shares - Non-option
Granted during the year (in shares)			2,325,000	1,620,000
KELTIP \| KELTIP Units \| Officers
Number of Shares - Non-option
Granted during the year (in shares)				1,620,000
Weighted Average Grant Date Fair Value Per Share - Non-option
Compensation expense \| $	$ 254,000			$ 334,000
Number of employees \| employee				2
Liability related to KELTIP Units \| $				$ 356,000
Additional compensation expense \| $	227,000
Modification of previously awarded KELTIP Units \| $	$ 583,000
Vesting immediately \| Equity Plan \| Restricted Stock \| Employees
Number of Shares - Non-option
Granted during the year (in shares)			104,000
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%
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%