v2.3.0.11
Fair Value Measurements (Details) (USD $)
 6 Months Ended 6 Months Ended 6 Months Ended
Jun. 25, 2011
Dec. 25, 2010
Jun. 25, 2011
Auction Rate Securities [Member]
Jun. 25, 2011
Level 1 [Member]
Dec. 25, 2010
Level 1 [Member]
Jun. 25, 2011
Level 2 [Member]
Dec. 25, 2010
Level 2 [Member]
Jun. 25, 2011
Level 3 [Member]
Dec. 25, 2010
Level 3 [Member]
Jun. 25, 2011
Level 3 (Unobservable Inputs) Closed-End Municipal Bond Funds, Student Loan Backed Auction-Rate Securities, Money Market Fund and Redeemable Noncontrolling Interests [Member]
Jun. 26, 2010
Level 3 (Unobservable Inputs) Closed-End Municipal Bond Funds, Student Loan Backed Auction-Rate Securities, Money Market Fund and Redeemable Noncontrolling Interests [Member]
Notes to Financial Statements [Abstract]                      
Number of levels in fair value hierarchy 3                    
Schedule of investments in auction-rate securities [Line Items]                      
Amount of investment     $ 12,900,000                
Investment net of temporary impairment     11,400,000                
Redemptions at par of auction-rate securities     2,200,000                
Minimum length of time to maturity on auction-rate securities (in years) 10                    
Maximum length of time to maturity on auction-rate securities (in years) 30                    
Minimum period for interest rates to reset on auction-rate securities (in days) 7                    
Additional period for interest rates to reset on auction-rate securities (in days) 28                    
Maximum period for interest rates to reset on auction-rate securities (in days) 35                    
Cumulative temporary impairment related to closed-end municipal bond funds and student loan portfolio   1,700,000                  
Change in cumulative temporary impairment related to closed-end municipal bond funds and student loan portfolio 200,000                    
Fair value of debt 443,300,000 441,300,000                  
Assets: [Abstracts]                      
Available-for-sale securities 11,405,000 13,367,000   0 0 0 0 11,405,000 13,367,000    
Derivative contracts - assets 1,463,000 1,213,000   0 0 1,463,000 1,213,000 0 0    
Total assets 12,868,000 14,580,000   0 0 1,463,000 1,213,000 11,405,000 13,367,000    
Liabilities: [Abstracts]                      
Derivative contracts - liabilities 1,057,000 2,771,000   0 0 1,057,000 2,771,000 0 0    
Total liabilities 1,057,000 2,771,000   0 0 1,057,000 2,771,000 0 0    
Redeemable Noncontrolling Interests [Abstract]                      
Redeemable noncontrolling interests 424,164,000 304,140,000   0 0 0 0 424,164,000 304,140,000    
Fair value of assets, liabilities and redeemable noncontrolling interests, unobservable input reconciliation [Line Items]                      
Fair value of assets, liabilities and redeemable noncontrolling interests, unobservable input reconciliation balance, beginning of period                   317,507,000 199,164,000
Change in redeemable noncontrolling interests                   120,024,000 162,529,000
Redemptions at par                   (2,150,000) (3,080,000)
Gain reported in accumulated other comprehensive income                   188,000 102,000
Fair value of assets, liabilities and redeemable noncontrolling interests, unobservable input reconciliation balance, end of period                   $ 435,569,000 $ 358,715,000