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The period of time, from the grant date until the time at which the share-based award expires.

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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.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested 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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Equity Compensation Plans - Options (Details) - USD ($)	3 Months Ended		12 Months Ended
Equity Compensation Plans - Options (Details) - USD ($)	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	May 31, 2019	Jun. 01, 2016	May 20, 2014
Equity Compensation Plans
Total compensation cost	$ 578,000	$ 401,000
Exercised (in shares)	4,500
Shares
Exercised (in shares)	(4,500)
Aggregate Intrinsic Value
Exercised (in dollars)	$ (27,000)
2014 Plan
Equity Compensation Plans
Number of shares authorized				600,000	975,000	375,000
Employee and Nonemployee Stock Options [Member]
Equity Compensation Plans
Granted (in shares)		0
Term of stock options granted	10 years
Exercised (in shares)	4,500	0
Total unrecognized compensation cost	$ 0
Shares
Beginning outstanding (in shares)	4,500
Exercised (in shares)	(4,500)	0
Ending outstanding (in shares)			4,500
Weighted Average Exercise Price
Beginning outstanding (in dollars per share)	$ 7.49
Exercised (in dollars per share)	$ 7.49
Ending outstanding (in dollars per share)			$ 7.49
Weighted Average Remaining Contractual Term (years)
Ending outstanding (in years)	0 years		1 month 6 days
Aggregate Intrinsic Value
Ending outstanding (in dollars)			$ 25,000
Restricted Stock and Restricted Stock Units [Member]
Equity Compensation Plans
Vesting period	3 years