Investments - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 29, 2012 Securities	Dec. 31, 2011	Dec. 25, 2010
Schedule of Available-for-sale Securities [Line Items]
Total realized gains on sales of AFS securities	$ 23,772,000	$ 35,864,000	$ 28,935,000
Total realized losses on sales of AFS securities	13,386,000	15,978,000	4,419,000
Other-than-temporary impairment losses		6,082,000
Total, Unrealized Losses	15,500,000	19,357,000
Number of AFS securities issues contributing to total unrealized loss	329
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Other-than-temporary impairment losses		6,082,000
Total, Unrealized Losses	$ 12,499,000	$ 14,274,000