Short-term and Long-term Obligations - Long-Term Obligations (Details) - Bank of America	1 Months Ended	6 Months Ended
	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) consecutive_quarter building
Minimum
Debt Instrument [Line Items]
Interest rate (as a percent)	0.79%	0.89%
Maximum
Debt Instrument [Line Items]
Interest rate (as a percent)	1.68%	1.74%
Term Loan
Debt Instrument [Line Items]
Term loan, face amount	$ 14,000,000
Number of buildings as collateral | building		3
Debt, total outstanding borrowings	$ 3,733,000	$ 2,333,000
Credit facility, term	5 years
Amount of assets as collateral for credit facility	$ 17,354,000	$ 17,239,000
Term Loan | LIBOR
Debt Instrument [Line Items]
Credit facility, basis spread on variable rate (as a percent)	1.50%
Bank of America Credit Agreement
Debt Instrument [Line Items]
Not to incur on a consolidated basis, a net loss before taxes and extraordinary items in any two consecutive quarterly accounting periods | consecutive_quarter		2
Bank of America Credit Agreement | Minimum
Debt Instrument [Line Items]
The Company's funded debt to EBITDA ratio (ratio of all outstanding liabilities for borrowed money and other interest-bearing liabilities, including current and long-term debt, less the non-current portion of subordinated liabilities to EBITDA), shall not be greater than		2.00
The Company's unencumbered liquid assets, as defined in the agreement, held in the United States shall have an aggregate market value, of not less than		$ 30,000,000