Investments (Summary Of Temporarily Impaired AFS Securities By The Time Period Impaired) (Details) (USD $)	Dec. 31, 2011	Dec. 25, 2010
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	$ 593,647,000	$ 809,778,000
Less Than 12 Months, Unrealized Losses	18,968,000	12,280,000
12 Months or Longer, Fair Value	7,915,000	7,755,000
12 Months or Longer, Unrealized Losses	389,000	1,272,000
Total, Fair Value	601,562,000	817,533,000
Total, Unrealized Losses	19,357,000	13,552,000
Tax Exempt Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	138,892,000	624,553,000
Less Than 12 Months, Unrealized Losses	536,000	8,321,000
12 Months or Longer, Fair Value	6,026,000	54,000
12 Months or Longer, Unrealized Losses	14,000	1,000
Total, Fair Value	144,918,000	624,607,000
Total, Unrealized Losses	550,000	8,322,000
Taxable Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	201,538,000	155,160,000
Less Than 12 Months, Unrealized Losses	1,514,000	2,045,000
12 Months or Longer, Fair Value		4,130,000
12 Months or Longer, Unrealized Losses		497,000
Total, Fair Value	201,538,000	159,290,000
Total, Unrealized Losses	1,514,000	2,542,000
Restricted Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	166,981,000
Less Than 12 Months, Unrealized Losses	3,019,000
Total, Fair Value	166,981,000
Total, Unrealized Losses	3,019,000
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	86,236,000	30,065,000
Less Than 12 Months, Unrealized Losses	13,899,000	1,914,000
12 Months or Longer, Fair Value	1,889,000	3,571,000
12 Months or Longer, Unrealized Losses	375,000	774,000
Total, Fair Value	88,125,000	33,636,000
Total, Unrealized Losses	$ 14,274,000	$ 2,688,000