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Long-Term Debt (Details Textual) - USD ($)			1 Months Ended	9 Months Ended
Long-Term Debt (Details Textual) - USD ($)	Nov. 03, 2017	Oct. 05, 2017	Aug. 18, 2015	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term Debt, Total				$ 35,287,000	$ 36,365,000
Amortization of Acquisition Costs				266,000
Affiliated Entity [Member]
Debt Instrument [Line Items]
Repayments of Secured Debt				$ 1,100,000
Secured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date				May 01, 2020
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				1.25%
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	$ 35,287,000	$ 35,287,000
Line of Credit Facility, Remaining Borrowing Capacity				$ 65,000,000
Revolving credit facility [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Repayments of Long-term Lines of Credit	$ 5,000,000	$ 5,287,000