Significant Customers and Contingencies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Revenue, Major Customer [Line Items]
Number of major customers	3
Accounts receivable	388,000	52,000
Customers One [Member]
Revenue, Major Customer [Line Items]
Accounts receivable	54,000	(308,000)
Customers One [Member] | Customer Concentration Risk [Member] | Sales [Member]
Revenue, Major Customer [Line Items]
Revenue from top customers	72.00%	72.00%
Customers Two [Member]
Revenue, Major Customer [Line Items]
Accounts receivable	0	0
Customers Two [Member] | Customer Concentration Risk [Member] | Sales [Member]
Revenue, Major Customer [Line Items]
Revenue from top customers	6.00%	3.00%
Customers Three [Member]
Revenue, Major Customer [Line Items]
Accounts receivable	47,000	46,000
Customers Three [Member] | Customer Concentration Risk [Member] | Sales [Member]
Revenue, Major Customer [Line Items]
Revenue from top customers	5.00%	6.00%
BASF [Member]
Revenue, Major Customer [Line Items]
Supply agreements with BASF Corporation	The financial condition covenants in one of our supply agreements with BASF “trigger” a technology transfer right (license and equipment sale at BASF’s option) in the event (a) that earnings for the twelve month period ending with our most recently published quarterly financial statements are less than zero and our cash, cash equivalents and certain investments are less than $1 million, or (b) of an acceleration of any debt maturity having a principal amount of more than $10 million.
Minimum contractual covenant - net earnings previous twelve months	0
Net book value equipment	115.00%
BASF [Member] | Maximum [Member]
Revenue, Major Customer [Line Items]
Cash, cash equivalents and investments, maximum	1,000,000
BASF [Member] | Minimum [Member]
Revenue, Major Customer [Line Items]
Principal amount of debt on maturity, minimum	10,000,000
Original book value of equipment, Minimum	30.00%