Debt - Other Long-Term Debt (Details)				12 Months Ended
	Jul. 14, 2011 USD ($)	Feb. 01, 2011 USD ($) job	Feb. 15, 2010 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Aug. 31, 2014 USD ($)	Dec. 20, 2013 USD ($)	Oct. 31, 2013 USD ($)	Mar. 06, 2013 USD ($)	Dec. 31, 2012 USD ($)	May. 20, 2010 USD ($) job	Apr. 30, 2010 USD ($) job	Aug. 31, 2009 USD ($) job
Debt Instrument [Line Items]
Current portion of long-term debt				$ 18,000	$ 84,000
Long-term debt				73,000	91,000
Loans Payable | August 2009, IDED Loans
Debt Instrument [Line Items]
Number of jobs required to create and retain for a specific period of time | job														20
Amount due if jobs not created														$ 150,000
Interest expense				7,100	6,800	$ 11,000
Loans Payable | August 2009, 5% IDED Loan
Debt Instrument [Line Items]
Debt face amount														$ 100,000
Debt stated interest rate														5.00%
Loans Payable | August 2009, $150,000 IDED Loan
Debt Instrument [Line Items]
Debt face amount														$ 150,000
Periodic payment minimum percentage of gross revenue														2.00%
Periodic payment annual principal payment minimum														$ 25,000
Periodic payment total expected payment														225,000
Expected principal payment in next fiscal year														$ 25,000
Current portion of long-term debt				18,000
Long-term debt				73,000
Loans Payable | April 2010, 1.625% Percent City of Ames Loan
Debt Instrument [Line Items]
Debt face amount													$ 100,000
Debt stated interest rate													1.625%
Number of jobs required to create for a specific period of time | job													62
Interest expense					300	1,000
Loans Payable | May 2010, Non-Interest Bearing IDED Loan
Debt Instrument [Line Items]
Debt face amount												$ 500,000
Number of jobs required to create and retain for a specific period of time | job												62
Forgivable Grant | February 2010, 6% IDED Forgivable Grant
Debt Instrument [Line Items]
Debt face amount			$ 150,000
Debt stated interest rate			6.00%
Debt term			10 years
Interest expense					9,000	11,000
Minimum percent of assets sold causing debt to no longer be forgivable			51.00%
Forgivable Grant | February 2011, 6% IDED Forgivable Grant
Debt Instrument [Line Items]
Debt face amount		$ 2,300,000
Debt stated interest rate		6.00%
Debt term		5 years
Number of jobs required to create and retain for a specific period of time | job		251
Forgivable Grant | October 2013, IEDA Loans
Debt Instrument [Line Items]
Debt face amount								$ 2,000,000
Forgivable Grant | October 2013, IEDA Forgivable Loans
Debt Instrument [Line Items]
Debt maximum amount available									$ 2,500,000
Forgivable Grant | October 2013, Non-interest Bearing IEDA Loan
Debt Instrument [Line Items]
Debt maximum amount available									$ 2,500,000
Line of Credit | Bankers Trust
Debt Instrument [Line Items]
Interest expense					0	0
Line of credit, maximum borrowing capacity	$ 1,000,000
Line of Credit | Bankers Trust | Prime Rate
Debt Instrument [Line Items]
Debt basis spread on variable rate	1.50%
Line of Credit | Morgan Stanley
Debt Instrument [Line Items]
Interest expense				0	16,000	27,000
Line of credit, maximum borrowing capacity										$ 20,800,000
Line of Credit | Silicon Valley Bank
Debt Instrument [Line Items]
Interest expense				0	28,000
Line of credit, maximum borrowing capacity							$ 15,000,000
Line of credit asset restrictions on cash				$ 5,000,000
Line of credit facility interest rate at period end				3.50%
Line of credit outstanding				$ 0
Line of Credit | February 2011, 6% IDED Forgivable Grant
Debt Instrument [Line Items]
Letter of credit oustanding				$ 2,300,000
Vehicle Financing Arrangements | 2012, 8.35% Vehicle Financing Arrangements
Debt Instrument [Line Items]
Debt face amount											$ 85,000
Debt stated interest rate											8.35%
Interest expense					$ 3,200	$ 5,400