The amount of expense recognized in the current period that reflects the allocation of capitalized costs associated with acquisition of business. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Long-Term Debt (Details Textual) - USD ($)			1 Months Ended	3 Months Ended
Long-Term Debt (Details Textual) - USD ($)	Nov. 03, 2017	Oct. 05, 2017	Aug. 18, 2015	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Amortization of Acquisition Costs				$ 266,000
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage				0.25%
Maximum [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage				0.30%
Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				1.00%
Minimum [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage				0.20%
Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				0.00%
Libor Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage				1.6875%
Libor Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				2.00%
Libor Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				1.00%
Revolving credit facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date			Aug. 18, 2020
Long-term Debt, Total			$ 100,000,000	$ 25,000,000	$ 25,000,000
Line of Credit Facility, Remaining Borrowing Capacity				$ 75,000,000
Repayments of Long-term Lines of Credit	$ 5,000,000	$ 5,287,000