Fair Value (Details 1) - Level 3 [Member] - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Risk-free interest rate	2.37%	2.20%
Expected life of option grants	5 years	5 years
Expected volatility of underlying stock		51.08%
Dividends assumption
Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Expected volatility of underlying stock	45.53%
Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Expected volatility of underlying stock	46.34%