CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Allowance for doubtful accounts		$ 1,045	$ 703
Common stock, par value		$ 0.0001	$ 0.0001
Common stock, shares authorized		125,047,000	119,547,000
Common stock, shares issued		26,503,000	24,429,000
Common stock, shares outstanding		26,503,000	24,429,000
Total assets	[1]	$ 2,240,750	$ 1,935,632
Solar energy systems, net		1,695,728	1,480,223
Cash and cash equivalents		116,610	152,154
Accounts receivable, net		49,619	43,189
Prepaid expenses and other current assets		16,698	9,560
Total liabilities	[1]	1,618,867	1,383,065
Accounts payable		69,566	51,166
Distributions payable to noncontrolling interests and redeemable noncontrolling interests		6,463	6,764
Accrued expenses and other liabilities		42,833	25,445
Long-term debt		337,722	239,251
Variable Interest Entities
Total assets		1,202,608	986,878
Solar energy systems, net		1,113,088	942,655
Cash and cash equivalents		72,983	29,099
Restricted cash		729	593
Accounts receivable, net		15,609	14,351
Prepaid expenses and other current assets		199	180
Total liabilities		504,377	474,348
Accounts payable		16,765	9,057
Distributions payable to noncontrolling interests and redeemable noncontrolling interests		6,413	6,426
Accrued expenses and other liabilities		162	340
Deferred revenue		329,114	301,792
Deferred grants		119,704	123,351
Long-term debt		$ 32,219	$ 33,382
Convertible Preferred Stock
Preferred stock, par value		$ 0.0001	$ 0.0001
Preferred stock, shares authorized		57,028,000	57,028,000
Preferred stock, shares issued		54,841,000	54,841,000
Preferred stock, shares outstanding		54,841,000	54,841,000
Aggregate liquidation preference		$ 305,883	$ 305,883

[1] The Company’s consolidated assets as of June 30, 2015 and December 31, 2014 include $1,202,608 (unaudited) and $986,878, respectively, in assets of variable interest entities, or VIEs, that can only be used to settle obligations of the VIEs. Solar energy systems, net, as of June 30, 2015 and December 31, 2014 were $1,113,088 (unaudited) and $942,655, respectively; cash and cash equivalents as of June 30, 2015 and December 31, 2014 were $72,983 (unaudited) and $29,099, respectively; restricted cash as of June 30, 2015 and December 31, 2014 were $729 (unaudited) and $593, respectively; accounts receivable, net as of June 30, 2015 and December 31, 2014 were $15,609 (unaudited) and $14,351. respectively; prepaid expenses and other current assets as of June 30, 2015 and December 31, 2014 were $199 (unaudited) and $180, respectively. The Company’s consolidated liabilities as of June 30, 2015 and December 31, 2014 include $504,377 (unaudited) and $474,348, respectively, in liabilities of VIEs whose creditors have no recourse to the Company. These liabilities include accounts payable as of June 30, 2015 and December 31, 2014 of $16,765 (unaudited) and $9,057, respectively; distributions payable to noncontrolling interests and redeemable noncontrolling interests as of June 30, 2015 and December 31, 2014 of $6,413 (unaudited) and $6,426, respectively; accrued expenses and other liabilities as of June 30, 2015 and December 31, 2014 of $162 (unaudited) and $340, respectively; deferred revenue as of June 30, 2015 and December 31, 2014 of $329,114 (unaudited) and $301,792, respectively; deferred grants as of June 30, 2015 and December 31, 2014 of $119,704 (unaudited) and $123,351, respectively; and long-term debt as of June 30, 2015 and December 31, 2014 of $32,219 (unaudited) and $33,382, respectively