Description of Business and Basis of Presentation - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015 Parties
Description Of Business And Basis Of Presentation [Line Items]
Coupons face value	$ 2,881
Number of related parties	2
Coupons issued to settle trade payable	219
Consulting Services Agreement [Member]
Description Of Business And Basis Of Presentation [Line Items]
Agreement termination notice period	3 months
Agreement term	3 years
Selling Expenses [Member]
Description Of Business And Basis Of Presentation [Line Items]
Coupons issued and recorded expenses	582
Call Option Agreement [Member]
Description Of Business And Basis Of Presentation [Line Items]
Agreement termination notice period	30 days
Solar Energy Ecommerce Shangai Limited [Member]
Description Of Business And Basis Of Presentation [Line Items]
Percentage of fund principal for commission fee	1.00%
Lease income earned	3
Solar Energy Ecommerce Shangai Limited [Member] | Minimum [Member]
Description Of Business And Basis Of Presentation [Line Items]
Lock-up period for investment	0 days
Annual rate of return on investment	8.00%
Solar Energy Ecommerce Shangai Limited [Member] | Maximum [Member]
Description Of Business And Basis Of Presentation [Line Items]
Lock-up period for investment	720 days
Annual rate of return on investment	10.30%
Third Party Vendors [Member]
Description Of Business And Basis Of Presentation [Line Items]
Coupons issued and recognized other receivable	1,301
Related Party [Member]
Description Of Business And Basis Of Presentation [Line Items]
Coupons issued and recognized other receivable	$ 779