Property, Plant and Equipment - Property, Plant and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Cost	$ 15,591	$ 15,727
Accumulated Depreciation	13,725	13,072
Net Book Value	1,866	2,655
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Cost	464	244
Accumulated Depreciation	292	212
Net Book Value	172	32
Office Furnishings, Fixtures and Other Assets [Member]
Property, Plant and Equipment [Line Items]
Cost	258	297
Accumulated Depreciation	192	169
Net Book Value	66	128
Research Equipment [Member]
Property, Plant and Equipment [Line Items]
Cost	3,461	3,767
Accumulated Depreciation	2,184	1,844
Net Book Value	1,277	1,923
Computer Hardware and Operating System [Member]
Property, Plant and Equipment [Line Items]
Cost	11,408	11,411
Accumulated Depreciation	11,057	10,839
Net Book Value	351	572
Commercial Manufacturing Equipment [Member]
Property, Plant and Equipment [Line Items]
Cost		8
Accumulated Depreciation		8
Net Book Value