Notes Receivable - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended	9 Months Ended						6 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Jun. 08, 2012	Dec. 31, 2011		Sep. 30, 2012 East Coast Company [Member]	Dec. 31, 2011 East Coast Company [Member]	Sep. 30, 2012 Solar Hub [Member]	Jun. 08, 2012 Solar Hub [Member]	Apr. 27, 2012 Solar Hub [Member]	Jun. 08, 2012 Secured Promissory Note [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest rate on advance		5.00%
Note receivable and Advance	$ 13,007	$ 13,007	$ 1,000	$ 5,862	[1]	$ 7,000	$ 5,900	$ 6,000		$ 1,000	$ 9,000
Note receivable annual interest rate	6.00%
Maturity date								December 31, 2013
Advance in cash

[1] As recast to reflect the balances of Solar Green Technology S.p.A. ("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 4-Acquisition of Solar Green Technology).