Supplementary Financial Data (Unaudited) (Details) - Quarterly Financial Information (USD $)
In Thousands, except Per Share data, unless otherwise specified
 3 Months Ended 12 Months Ended
Dec. 29, 2013
Sep. 29, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 30, 2012
Sep. 30, 2012
Jul. 01, 2012
Mar. 25, 2012
Dec. 29, 2013
Dec. 30, 2012
Dec. 25, 2011
Quarterly Financial Information [Abstract]                      
Net sales (1) $ 313,670 [1] $ 273,378 [1] $ 195,070 [1] $ 189,572 [1] $ 223,987 [1] $ 239,747 [1] $ 233,440 [1] $ 218,758 [1] $ 971,690 $ 915,932 $ 1,069,883
Cost of sales 220,422 217,209 137,714 143,717 152,047 161,281 159,529 159,560 719,062 632,417 847,797
Gross profit 93,248 56,169 57,356 45,855 71,940 78,466 73,911 59,198 252,628 283,515 222,086
Research and development (1) 42,102 [1] 38,341 [1] 23,548 [1] 22,777 [1] 24,771 [1] 27,407 [1] 29,631 [1] 26,041 [1] 126,768 107,850 106,644
Sales, general and administrative (1) 60,824 [1] 54,544 [1] 34,414 [1] 28,483 [1] 32,121 [1] 35,228 [1] 35,617 [1] 32,640 [1]      
Net gain on sale of Kuala Lampur land and building             (28,434)        
Restructuring charges (credits) (247) 6,264       1,862 (729) 4,518      
Operating income (loss) (9,431) (42,980) (606) (5,405) 15,048 13,969 37,826 (4,001)      
Interest and other income (expense), net (2) (3,252) [2] 3,578 [2] 3,118 [2] 962 [2] 2,472 [2] 1,267 [2] (556) [2] 1,505 [2] 4,406 4,688 3,954
Interest expense (7,459) (7,351) (7,378) (7,604) (7,224) (7,339) (7,903) (7,681) (29,792) (30,147) (33,151)
Gain (loss) on acquisition of Microcontroller and Analog business (3) (255) [3] 8,205 [3]    [3]    [3]    [3]    [3]    [3]    [3]      
Income (loss) before income taxes (20,397) (38,548) (4,866) (12,047) 10,296 7,897 29,367 (10,177) (75,858) 37,383 (34,511)
(Provision) benefit for income taxes (3,301) 1,644 1,635 (2,388) (3,428) (2,757) (3,370) (3,445) (2,410) (12,999) (21,037)
Net income (loss) (23,698) (36,904) (3,231) (14,435) 6,868 5,140 25,997 (13,622) (78,268) 24,384 (55,548)
Less: Net income (loss) attributable to the noncontrolling interest               (503)   (503) 338
Net income(loss) attributable to Spansion Inc. common stockholders $ (23,698) $ (36,904) $ (3,231) $ (14,435) $ 6,868 $ 5,140 $ 25,997 $ (13,119) $ (78,268) $ 24,887 $ (55,886)
Net income (loss) per share                      
Basic (in Dollars per share) $ (0.40) $ (0.63) $ (0.06) $ (0.25) $ 0.11 $ 0.09 $ 0.43 $ (0.22) $ (1.34) $ 0.41 $ (0.91)
Diluted (in Dollars per share) $ (0.40) $ (0.63) $ (0.06) $ (0.25) $ 0.11 $ 0.08 $ 0.43 $ (0.22) $ (1.34) $ 0.41 $ (0.91)
Shares used in per share calculateion                      
Basic (in Shares) 58,878 58,785 58,646 58,086 60,144 60,139 59,975 59,676 58,599 59,984 61,338
Diluted (in Shares) 58,878 58,785 58,646 58,086 61,487 60,820 60,475 59,676 58,599 61,021 61,338
[1] The increase for the quarter ended September 29, 2013 and December 29, 2013 are mainly due to the acquisition of the MCA business
[2] The decrease for the quarter ended December 29, 2013 is due to $5.3M higher realized, unrealized loss on foreign currency transactions in the fourth quarter of fiscal 2013
[3] The gain for the quarter ended September 29, 2013 and December 29, 2013, relates to the gain and related adjustments on acquistion of the MCA business. The accounting guidance requires that the economic gain resulting from the fair value received being greater than the consideration paid to acquire the net assets to be recorded as an one-time gain included in earnings.