Condensed Consolidated Statements of Income (USD $)
In Thousands, except Per Share data
 3 Months Ended 9 Months Ended
May 31, 2011
May 31, 2010
May 31, 2011
May 31, 2010
Revenues:        
Company-owned Drive-In sales $ 113,745 $ 108,752 $ 297,454 $ 298,963
Franchise Drive-Ins:        
Franchise royalties 34,825 32,807 88,650 86,621
Franchise fees 385 854 1,271 1,936
Lease revenue 1,828 2,264 4,347 5,085
Other 1,315 1,368 3,045 3,250
Total revenues 152,098 146,045 394,767 395,855
Costs and expenses:        
Food and packaging 31,996 30,031 83,559 82,393
Payroll and other employee benefits 40,169 39,427 108,068 105,140
Other operating expenses, exclusive of depreciation and amortization included below 23,549 23,820 66,765 69,541
Total costs and expenses 95,714 93,278 258,392 257,074
Selling, general and administrative 17,212 17,096 48,778 50,552
Depreciation and amortization 10,139 10,645 30,806 31,958
Provision for impairment of long-lived assets 49 188 313 188
Total operating expenses 123,114 121,207 338,289 339,772
Other operating income (expense), net (20) (184) 255 (706)
Income from operations 28,964 24,654 56,733 55,377
Interest expense 7,991 9,036 24,414 28,426
Interest income (161) (251) (513) (744)
Net loss from early extinguishment of debt 28,230 314 23,025 314
Net interest expense 36,060 9,099 46,926 27,996
Income (loss) before income taxes (7,096) 15,555 9,807 27,381
Provision (benefit) for income taxes (2,742) 3,450 2,195 6,538
Net income (loss) - including noncontrolling interests (4,354) 12,105 7,612 20,843
Net income - noncontrolling interests 297 1,139 673 4,289
Net income (loss) - attributable to Sonic Corp. $ (4,651) $ 10,966 $ 6,939 $ 16,554
Basic income (loss) per share $ (0.08) $ 0.18 $ 0.11 $ 0.27
Diluted income (loss) per share $ (0.08) $ 0.18 $ 0.11 $ 0.27