Restricted Stock Units (RSU) (Details) - RSUs currently issued or forfeited - Restricted Stock Units (RSUs) [Member] - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted Stock Units (RSU) (Details) - RSUs currently issued or forfeited [Line Items]
Closing Stock Price (in Dollars per share)	$ 19.26	$ 17.00	$ 13.00
Vesting Date	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Time Based RSUs [Member]
Restricted Stock Units (RSU) (Details) - RSUs currently issued or forfeited [Line Items]
Balance	8,717	6,077
Issued	3,172	4,044	6,077
Excercised
Forfeited		(1,404)
Balance	11,889	8,717	6,077
Targeted Performance Based RSUs [Member]
Restricted Stock Units (RSU) (Details) - RSUs currently issued or forfeited [Line Items]
Balance	5,000
Issued	4,781	5,750
Excercised
Forfeited		(750)
Balance	9,781	5,000

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

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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Number of options outstanding, including both vested and non-vested options.

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Per share or per unit amount of equity securities issued.

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