Note 13 - Stock-based Compensation (Detail) - Consolidated Stock-Based Compensation by Line Items (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Stock-based compensation expense	$ 455,000	$ 461,000	[1]
Tax effect on stock-based compensation expense	0	0	[1]
Total stock-based compensation expense after income taxes	455,000	461,000	[1]
Advertising Expense [Member]
Stock-based compensation expense	394,000	425,000	[1]
Selling and Marketing Expense [Member]
Stock-based compensation expense	57,000	29,000	[1]
Engineering Design and Product Development [Member]
Stock-based compensation expense	$ 4,000	$ 7,000	[1]

[1] As recast to reflect the activity of SGT beginning January 1, 2011 combined with the balances of Solar Power, Inc. beginning March 31, 2011, as required under the accounting guidelines for a transfer of an entity under common control (refer to Note 5 -Acquisition of Solar Green Technology ).