Joint Ventures	3 Months Ended
Apr. 01, 2012
Equity Method Investments and Joint Ventures [Abstract]
Joint Ventures [Text Block]	JOINT VENTURES Joint Venture with Woongjin Energy Co., Ltd ("Woongjin Energy") The Company and Woongjin Holdings Co., Ltd. ("Woongjin") formed Woongjin Energy in fiscal 2006, a joint venture to manufacture monocrystalline silicon ingots in Korea. The Company supplies polysilicon, services, and technical support required for silicon ingot manufacturing to Woongjin Energy. Once manufactured, the Company purchases the silicon ingots from Woongjin Energy under a nine-year agreement through 2016. There is no obligation or expectation for the Company to provide additional funding to Woongjin Energy. On June 30, 2010, Woongjin Energy completed its initial public offering ("IPO") and the sale of 15.9 million new shares of common stock. As a result of the completion of the IPO, the Company concluded that Woongjin Energy is no longer a variable interest entity ("VIE"). During the second half of fiscal 2011, the Company sold 15.5 million shares of Woongjin Energy on the open market subsequently reducing the Company's percentage equity ownership in Woongjin Energy from 31% to 6%. As of January 1, 2012, the Company held 3.9 million shares of Woongjin Energy. During the first quarter of fiscal 2012, the Company sold its remaining shares of Woongjin Energy on the open market for total proceeds, net of tax, amounting to $14.0 million, which equaled the remaining investment carrying balance. As a result, the Company's percentage equity ownership and investment carrying balance was reduced to zero. During the first quarter of fiscal 2012, the Company collected $3.4 million of net proceeds associated with fiscal 2011 sales, the balance of which is included in "Prepaid expenses and other current assets" on the Company's Condensed Consolidated Balance Sheet as of January 1, 2012 due to timing of cash settlement for trades executed near year end. As of April 1, 2012 and January 1, 2012, the Company's carrying value of its investment in Woongjin Energy totaled zero and $14.0 million, respectively, in its Condensed Condensed Consolidated Balance Sheets. The Company accounted for its former investment in Woongjin Energy using the equity method as the Company was able to exercise significant influence over Woongjin Energy due to its board position and its consumption of a significant portion of their output. The Company's former investment is classified as "Other long-term assets" in the Condensed Consolidated Balance Sheets as of January 1, 2012 and the Company's share of Woongjin Energy's income totaling zero and $4.5 million for the three months ended April 1, 2012 and April 3, 2011, respectively, is included in "Equity in earnings (loss) of unconsolidated investees" in the Condensed Consolidated Statements of Operations. As of April 1, 2012 and January 1, 2012, $16.2 million and $24.4 million, respectively, remained due and receivable from Woongjin Energy related to polysilicon the Company supplied to Woongjin Energy for silicon ingot manufacturing. Payments to Woongjin Energy for manufactured silicon ingots totaled $59.6 million and $48.8 million during the three months ended April 1, 2012 and April 3, 2011, respectively. As of April 1, 2012 and January 1, 2012, $19.3 million and $44.1 million, respectively, remained due and payable to Woongjin Energy. Joint Venture with First Philec Solar Corporation ("First Philec Solar") The Company and First Philippine Electric Corporation ("First Philec") formed First Philec Solar in fiscal 2007, a joint venture to provide wafer slicing services of silicon ingots to the Company in the Philippines. The Company supplies to First Philec Solar silicon ingots and technology required for slicing silicon. Once manufactured, the Company purchases the completed silicon wafers from First Philec Solar under a six-year wafering supply and sales agreement through 2013. There is no obligation or expectation for the Company to provide additional funding to First Philec Solar. As of both April 1, 2012 and January 1, 2012, the Company's carrying value of its investment in the joint venture totaled $6.9 million in its Condensed Consolidated Balance Sheets which represented a 15% equity investment in both periods. The Company accounts for its investment in First Philec Solar using the equity method since the Company is able to exercise significant influence over First Philec Solar due to its board positions. The Company's investment is classified as "Other long-term assets" in the Condensed Consolidated Balance Sheets and the Company's share of First Philec Solar's income of zero and $0.5 million for the three months ending April 1, 2012 and April 3, 2011, respectively, is included in “Equity in earnings (loss) of unconsolidated investees” in the Condensed Consolidated Statements of Operations. As of April 1, 2012, the Company's maximum exposure to loss as a result of its involvement with First Philec Solar was limited to the carrying value of its investment. As of April 1, 2012 and January 1, 2012, $8.9 million and $8.1 million, respectively, remained due and receivable from First Philec Solar related to the wafer slicing process of silicon ingots supplied by the Company to First Philec Solar. Payments to First Philec Solar for wafer slicing services of silicon ingots totaled $24.0 million and $28.4 million during the three months ended April 1, 2012 and April 3, 2011, respectively. As of April 1, 2012 and January 1, 2012, $9.8 million and $8.0 million, respectively, remained due and payable to First Philec Solar related to the purchase of silicon wafers. The Company has concluded that it is not the primary beneficiary of First Philec Solar since, although the Company and First Philec are both obligated to absorb losses or have the right to receive benefits from First Philec Solar that are significant to First Philec Solar, such variable interests held by the Company do not empower it to direct the activities that most significantly impact First Philec Solar's economic performance. In reaching this determination, the Company considered the significant control exercised by First Philec over the joint venture's Board of Directors, management and daily operations. Joint Venture with AUOSP The Company, through its subsidiaries SunPower Technology, Ltd. ("SPTL") formed the joint venture AUOSP, formerly SunPower Malaysia Manufacturing Sdn. Bhd., with AUO and AU Optronics Corporation, the ultimate parent company of AUO ("AUO Taiwan") in the third quarter of fiscal 2010. The Company, through SPTL, and AUO each own 50% of the joint venture AUOSP. AUOSP owns a solar cell manufacturing facility ("FAB 3") in Malaysia and manufactures solar cells and sells them on a "cost-plus" basis to the Company and AUO. In connection with the joint venture agreement, the Company and AUO also entered into licensing and joint development, supply, and other ancillary transaction agreements. Through the licensing agreement, SPTL and AUO licensed to AUOSP, on a non-exclusive, royalty-free basis, certain background intellectual property related to solar cell manufacturing (in the case of SPTL), and manufacturing processes (in the case of AUO). Under the seven-year supply agreement with AUOSP, renewable by the Company for one-year periods thereafter, the percentage of AUOSP's total annual output allocated on a monthly basis to the Company, which the Company is committed to purchase, ranges from 95% in the fourth quarter of fiscal 2010 to 80% in fiscal year 2013 and thereafter. The Company and AUO have the right to reallocate supplies from time to time under a written agreement. As required under the joint venture agreement, in fiscal 2010, the Company and AUOSP entered into an agreement under which the Company will resell to AUOSP polysilicon purchased from a third-party supplier and AUOSP will provide prepayments to the Company related to such polysilicon, which prepayment will then be made by the Company to the third-party supplier. The Company and AUO are not permitted to transfer any of AUOSP's shares held by them, except to each other and to their direct or indirect wholly-owned subsidiaries. The Company and AUO will each contribute additional amounts through 2014 amounting to $241.0 million, or such lesser amount as the parties may mutually agree. In addition, if AUOSP, SPTL or AUO requests additional equity financing to AUOSP, then SPTL and AUO will each be required to make additional cash contributions of up to $50.0 million in the aggregate (See Note 8). The Company has concluded that it is not the primary beneficiary of AUOSP since, although the Company and AUO are both obligated to absorb losses or have the right to receive benefits, the Company alone does not have the power to direct the activities of AUOSP that most significantly impact its economic performance. In making this determination the Company considered the shared power arrangement, including equal board governance for significant decisions, elective appointment, and the fact that both parties contribute to the activities that most significantly impact the joint venture's economic performance. As a result of the shared power arrangement the Company deconsolidated AUOSP in the third quarter of fiscal 2010 and accounts for its investment in the joint venture under the equity method. As of April 1, 2012 and January 1, 2012, the Company's carrying value of its investment (which represents its 50% equity investment) totaled $105.6 million and $109.0 million, respectively, in its Condensed Consolidated Balance Sheets. The Company accounts for its investment in AUOSP using the equity method in which the investment is classified as "Other long-term assets" in the Condensed Consolidated Balance Sheets. The Company's share of AUOSP's net loss for the three months ended April 1, 2012 totaled $3.4 million and its share of AUOSP's net income for the three months ended April 3, 2011 totaled $2.2 million, which is included in "Equity in earnings (loss) of unconsolidated investees" in the Condensed Consolidated Statement of Operations. The Company accounts for its share of AUOSP's net income (loss) with a quarterly lag in reporting. As of April 1, 2012 and January 1, 2012, $33.9 million, and $66.4 million, respectively, remained due and receivable from AUOSP and $81.2 million and $101.7 million, respectively, remained due and payable to AUOSP. Payments to AUOSP for solar cells totaled $156.0 million and $27.9 million during the three months ended April 1, 2012 and April 3, 2011, respectively. As of April 1, 2012, the Company's maximum exposure to loss as a result of its involvement with AUOSP is limited to the carrying value of its investment.

JOINT VENTURES

Joint Venture with Woongjin Energy Co., Ltd ("Woongjin Energy")

The Company and Woongjin Holdings Co., Ltd. ("Woongjin") formed Woongjin Energy in fiscal 2006, a joint venture to manufacture monocrystalline silicon ingots in Korea. The Company supplies polysilicon, services, and technical support required for silicon ingot manufacturing to Woongjin Energy. Once manufactured, the Company purchases the silicon ingots from Woongjin Energy under a nine-year agreement through 2016. There is no obligation or expectation for the Company to provide additional funding to Woongjin Energy.

On June 30, 2010, Woongjin Energy completed its initial public offering ("IPO") and the sale of 15.9 million new shares of common stock. As a result of the completion of the IPO, the Company concluded that Woongjin Energy is no longer a variable interest entity ("VIE"). During the second half of fiscal 2011, the Company sold 15.5 million shares of Woongjin Energy on the open market subsequently reducing the Company's percentage equity ownership in Woongjin Energy from 31% to 6%. As of January 1, 2012, the Company held 3.9 million shares of Woongjin Energy. During the first quarter of fiscal 2012, the Company sold its remaining shares of Woongjin Energy on the open market for total proceeds, net of tax, amounting to $14.0 million, which equaled the remaining investment carrying balance. As a result, the Company's percentage equity ownership and investment carrying balance was reduced to zero. During the first quarter of fiscal 2012, the Company collected $3.4 million of net proceeds associated with fiscal 2011 sales, the balance of which is included in "Prepaid expenses and other current assets" on the Company's Condensed Consolidated Balance Sheet as of January 1, 2012 due to timing of cash settlement for trades executed near year end.

As of April 1, 2012 and January 1, 2012, the Company's carrying value of its investment in Woongjin Energy totaled zero and $14.0 million, respectively, in its Condensed Condensed Consolidated Balance Sheets. The Company accounted for its former investment in Woongjin Energy using the equity method as the Company was able to exercise significant influence over Woongjin Energy due to its board position and its consumption of a significant portion of their output. The Company's former investment is classified as "Other long-term assets" in the Condensed Consolidated Balance Sheets as of January 1, 2012 and the Company's share of Woongjin Energy's income totaling zero and $4.5 million for the three months ended April 1, 2012 and April 3, 2011, respectively, is included in "Equity in earnings (loss) of unconsolidated investees" in the Condensed Consolidated Statements of Operations.

As of April 1, 2012 and January 1, 2012, $16.2 million and $24.4 million, respectively, remained due and receivable from Woongjin Energy related to polysilicon the Company supplied to Woongjin Energy for silicon ingot manufacturing. Payments to Woongjin Energy for manufactured silicon ingots totaled $59.6 million and $48.8 million during the three months ended April 1, 2012 and April 3, 2011, respectively. As of April 1, 2012 and January 1, 2012, $19.3 million and $44.1 million, respectively, remained due and payable to Woongjin Energy.

Joint Venture with First Philec Solar Corporation ("First Philec Solar")

The Company and First Philippine Electric Corporation ("First Philec") formed First Philec Solar in fiscal 2007, a joint venture to provide wafer slicing services of silicon ingots to the Company in the Philippines. The Company supplies to First Philec Solar silicon ingots and technology required for slicing silicon. Once manufactured, the Company purchases the completed silicon wafers from First Philec Solar under a six-year wafering supply and sales agreement through 2013. There is no obligation or expectation for the Company to provide additional funding to First Philec Solar.

As of both April 1, 2012 and January 1, 2012, the Company's carrying value of its investment in the joint venture totaled $6.9 million in its Condensed Consolidated Balance Sheets which represented a 15% equity investment in both periods. The Company accounts for its investment in First Philec Solar using the equity method since the Company is able to exercise significant influence over First Philec Solar due to its board positions. The Company's investment is classified as "Other long-term assets" in the Condensed Consolidated Balance Sheets and the Company's share of First Philec Solar's income of zero and $0.5 million for the three months ending April 1, 2012 and April 3, 2011, respectively, is included in “Equity in earnings (loss) of unconsolidated investees” in the Condensed Consolidated Statements of Operations. As of April 1, 2012, the Company's maximum exposure to loss as a result of its involvement with First Philec Solar was limited to the carrying value of its investment.

As of April 1, 2012 and January 1, 2012, $8.9 million and $8.1 million, respectively, remained due and receivable from First Philec Solar related to the wafer slicing process of silicon ingots supplied by the Company to First Philec Solar. Payments to First Philec Solar for wafer slicing services of silicon ingots totaled $24.0 million and $28.4 million during the three months ended April 1, 2012 and April 3, 2011, respectively. As of April 1, 2012 and January 1, 2012, $9.8 million and $8.0 million, respectively, remained due and payable to First Philec Solar related to the purchase of silicon wafers.

The Company has concluded that it is not the primary beneficiary of First Philec Solar since, although the Company and First Philec are both obligated to absorb losses or have the right to receive benefits from First Philec Solar that are significant to First Philec Solar, such variable interests held by the Company do not empower it to direct the activities that most significantly impact First Philec Solar's economic performance. In reaching this determination, the Company considered the significant control exercised by First Philec over the joint venture's Board of Directors, management and daily operations.

Joint Venture with AUOSP

The Company, through its subsidiaries SunPower Technology, Ltd. ("SPTL") formed the joint venture

AUOSP, formerly SunPower Malaysia Manufacturing Sdn. Bhd., with AUO and AU Optronics Corporation, the ultimate parent company of AUO ("AUO Taiwan") in the third quarter of fiscal 2010. The Company, through SPTL, and AUO each own 50% of the joint venture AUOSP. AUOSP owns a solar cell manufacturing facility ("FAB 3") in Malaysia and manufactures solar cells and sells them on a "cost-plus" basis to the Company and AUO.

In connection with the joint venture agreement, the Company and AUO also entered into licensing and joint development, supply, and other ancillary transaction agreements. Through the licensing agreement, SPTL and AUO licensed to AUOSP, on a non-exclusive, royalty-free basis, certain background intellectual property related to solar cell manufacturing (in the case of SPTL), and manufacturing processes (in the case of AUO). Under the seven-year supply agreement with AUOSP, renewable by the Company for one-year periods thereafter, the percentage of AUOSP's total annual output allocated on a monthly basis to the Company, which the Company is committed to purchase, ranges from 95% in the fourth quarter of fiscal 2010 to 80% in fiscal year 2013 and thereafter. The Company and AUO have the right to reallocate supplies from time to time under a written agreement. As required under the joint venture agreement, in fiscal 2010, the Company and AUOSP entered into an agreement under which the Company will resell to AUOSP polysilicon purchased from a third-party supplier and AUOSP will provide prepayments to the Company related to such polysilicon, which prepayment will then be made by the Company to the third-party supplier.

The Company and AUO are not permitted to transfer any of AUOSP's shares held by them, except to each other and to their direct or indirect wholly-owned subsidiaries. The Company and AUO will each contribute additional amounts through 2014 amounting to $241.0 million, or such lesser amount as the parties may mutually agree. In addition, if AUOSP, SPTL or AUO requests additional equity financing to AUOSP, then SPTL and AUO will each be required to make additional cash contributions of up to $50.0 million in the aggregate (See Note 8).

The Company has concluded that it is not the primary beneficiary of AUOSP since, although the Company and AUO are both obligated to absorb losses or have the right to receive benefits, the Company alone does not have the power to direct the activities of AUOSP that most significantly impact its economic performance. In making this determination the Company considered the shared power arrangement, including equal board governance for significant decisions, elective appointment, and the fact that both parties contribute to the activities that most significantly impact the joint venture's economic performance. As a result of the shared power arrangement the Company deconsolidated AUOSP in the third quarter of fiscal 2010 and accounts for its investment in the joint venture under the equity method.

As of April 1, 2012 and January 1, 2012, the Company's carrying value of its investment (which represents its 50% equity investment) totaled $105.6 million and $109.0 million, respectively, in its Condensed Consolidated Balance Sheets. The Company accounts for its investment in AUOSP using the equity method in which the investment is classified as "Other long-term assets" in the Condensed Consolidated Balance Sheets. The Company's share of AUOSP's net loss for the three months ended April 1, 2012 totaled $3.4 million and its share of AUOSP's net income for the three months ended April 3, 2011 totaled $2.2 million, which is included in "Equity in earnings (loss) of unconsolidated investees" in the Condensed Consolidated Statement of Operations. The Company accounts for its share of AUOSP's net income (loss) with a quarterly lag in reporting.

As of April 1, 2012 and January 1, 2012, $33.9 million, and $66.4 million, respectively, remained due and receivable from AUOSP and $81.2 million and $101.7 million, respectively, remained due and payable to AUOSP. Payments to AUOSP for solar cells totaled $156.0 million and $27.9 million during the three months ended April 1, 2012 and April 3, 2011, respectively. As of April 1, 2012, the Company's maximum exposure to loss as a result of its involvement with AUOSP is limited to the carrying value of its investment.