Stock-Based Compensation - Schedule of Outstanding Restricted Stock Units (Details) - Restricted Stock Units (RSUs) - shares	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Non-vested Shares [Roll Forward]
Non-vested RSUs at beginning of period (in shares)	728,909
Granted, Shares (in shares)	592,500
Vested (in shares)	(284,200)
Forfeited (in shares)	(7,500)
Non-vested RSUs at end of period (in shares)	1,029,709	728,909
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Non-vested RSUs, Weighted Average Remaining Contractual Term (in years)	2 years 3 months 18 days	2 years 2 months 12 days
Granted non-vested options, Weighted Average Remaining Contractual Term (in years)	2 years 9 months 18 days