Note 10 - Business Segment Information (Detail) - Revenues and Accounts Receivable by Major Customers (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Sales	$ 454	$ 476	$ 711	$ 3,027
Hybricon [Member] | Power And Energy Group [Member]
Sales			131
ABB Secheron [Member] | Power And Energy Group [Member]
Sales			98
Cargotec [Member] | Power And Energy Group [Member]
Sales			90
Bombardier [Member] | Power And Energy Group [Member]
Sales			79
Accounts Receivable	79		79
Ocean Power Te [Member] | Power And Energy Group [Member]
Sales			74
Yintong Energy (YTE) [Member] | Power And Energy Group [Member]
Sales				1,713
Accounts Receivable		15		15
Proterra, LLC [Member] | Power And Energy Group [Member]
Sales				512
US Army [Member] | All Other Segments [Member]
Sales				303
Accounts Receivable		116		116
Power And Energy Group [Member]
Sales	394	229	591	2,525
All Other Segments [Member]
Sales	$ 60	$ 247	$ 120	$ 502