6. Restricted Cash and Investments (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2014		Dec. 31, 2013
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted securities, gross unrealized losses	$ 482,000		$ 662,000
Restricted Cash, Current	500,000		0
Restricted Cash, Noncurrent	1,645,000	[1]	167,000	[1]
Restricted Investments, Noncurrent	303,112,000		279,274,000
Restricted cash and investments	304,757,000		279,441,000
Solar Module Collection And Recycling Custodial Account	90 days
Product Minimum Service Life	25 years
Restricted Investments [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted securities, gross unrealized losses	$ 1,038,000		$ 5,793,000

[1] There was $0.5 million and zero of restricted cash included within prepaid expenses and other current assets at March 31, 2014 and December 31, 2013, respectively, primarily related to required cash collateral for certain letters of credit provided for projects under development in foreign jurisdictions.