Long-term Debt, Line of Credit and Derivatives - Obligations under Debt Arrangements (Details) - USD ($) $ in Thousands	1 Months Ended				6 Months Ended
	Jun. 30, 2020	May 31, 2019	Mar. 31, 2019	Jul. 31, 2018	Jun. 30, 2020	Jun. 30, 2019	Jun. 08, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Amortization of debt issuance costs					$ 286	$ 186
Principal current	$ 4,500				4,500			$ 3,750
Principal, long-term	49,290				49,290			69,540
Principal	53,790				53,790			73,290
Deferred Issuance Costs, current	(142)				(142)			(82)
Deferred Issuance Costs, long-term	(1,556)				(1,556)			(1,511)
Debt Issuance Costs, Net, Total	(1,698)				(1,698)			(1,593)
Net Value, current	4,358				4,358			3,668
Net Value, long-term	47,734				47,734			68,029
Total debt	$ 52,092				$ 52,092			71,697
Line of Credit
Debt Instrument [Line Items]
Weighted average interest rate	3.15%				3.15%
Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 50,000				$ 50,000
Debt issuance expense		$ 400
Principal, long-term	18,000				18,000			36,000
Deferred Issuance Costs, long-term	(568)				(568)			(782)
Net Value, long-term	17,432				17,432			35,218
Term Loan | Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	60,000				60,000
Principal current	4,500				4,500			3,750
Principal, long-term	31,290				31,290			33,540
Principal	35,790				35,790
Deferred Issuance Costs, current	(142)				(142)			(82)
Deferred Issuance Costs, long-term	(988)				(988)			(729)
Net Value, current	4,358				4,358			3,668
Net Value, long-term	30,302				30,302			$ 32,811
364-Day Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity							$ 20,000
Debt issuance expense	400
Fourth, Fifth And Sixth Amendments To Credit Agreement | Line of Credit
Debt Instrument [Line Items]
Debt Issuance Costs, Net, Total	$ (900)				$ (900)
Fourth Amendment to Credit Agreement | Line of Credit
Debt Instrument [Line Items]
Debt issuance cost				$ 900
Fifth Amendment To Credit Agreement | Line of Credit
Debt Instrument [Line Items]
Debt issuance cost			$ 600
Sixth Amendment To Credit Agreement | Line of Credit
Debt Instrument [Line Items]
Debt issuance cost		$ 900