Debt (Details Textual)						1 Months Ended	12 Months Ended
	Feb. 27, 2017 USD ($)	Oct. 31, 2016 USD ($)	Dec. 23, 2014 USD ($) covenant	Jan. 17, 2014 USD ($)	Jan. 19, 2010 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Mar. 15, 2017 USD ($)
Line of Credit Facility [Line Items]
Date of first required payment					Jan. 19, 2010
Description of variable rate basis							One-month LIBOR rate
Proceeds from term loan							$ 3,600,000	$ 0	$ 0
Current portion of debt (Note 5)							3,600,000	0
SunTrust Bank [Member]
Line of Credit Facility [Line Items]
Period of term loan and the revolving credit facility					4 years
Revolving credit facility and term loan interest rate (percent)						2.43%				2.43%
Revolving credit facility commitment fee (percent)										0.50%
SunTrust Bank [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Applicable margin (percent)										2.25%
SunTrust Bank [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Applicable margin (percent)										3.50%
SunTrust Bank [Member] | LIBOR [Member]
Line of Credit Facility [Line Items]
Variable interest rate, term										1 month
Applicable margin (percent)										2.25%
Sun Trust Revolving Credit Facility
Line of Credit Facility [Line Items]
Proceeds from term loan		$ 3,600,000
Current portion of debt (Note 5)							3,600,000
Sun Trust Revolving Credit Facility | SunTrust Bank [Member]
Line of Credit Facility [Line Items]
Committed revolving credit facility			$ 20,000,000.0	$ 25,000,000	$ 15,000,000.0
Revolving credit facility commitment fee (percent)			0.25%	0.50%
Fixed interest rate (percent)				1.75%
Number of debt covenants | covenant			2
Term for debt covenants to apply (last days of fiscal quarter)			30 days
Future minimum principal payments							$ 0	$ 0
Sun Trust Revolving Credit Facility | SunTrust Bank [Member] | LIBOR [Member]
Line of Credit Facility [Line Items]
Applicable margin (percent)			1.75%
Sun Trust Term Loan
Line of Credit Facility [Line Items]
Date of first required payment							Mar. 31, 2010
Frequency of periodic payment							Quarterly
Sun Trust Term Loan | SunTrust Bank [Member]
Line of Credit Facility [Line Items]
Committed term loan					15,000,000.0
Revolving credit facility, quarterly principal payment					$ 800,000
Final principal payment						$ 3,000,000				$ 3,000,000
Term loan, weighted average interest rate (percent)						4.10%	0.25%	0.25%		4.10%
Mandatory principal payments on SunTrust term loan										$ 3,000,000
Subsequent Event | Sun Trust Revolving Credit Facility
Line of Credit Facility [Line Items]
Proceeds from term loan	$ 10,000,000
Line of Credit Facility, Fair Value of Amount Outstanding											$ 13,600,000