Schedule of Fixed Income Securities in Unrealized Loss Positions (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 29, 2013
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	$ 526,537
Unrealized Losses Less Than 12 Months - Unrealized	(1,668)
Unrealized Losses 12 Months or Greater - Fair Value	12,515
Unrealized Losses 12 Months or Greater - Unrealized	(175)
Total - Fair Value	539,052
Total - Unrealized	(1,843)
Municipal Notes And Bonds
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	22,814
Unrealized Losses Less Than 12 Months - Unrealized	(47)
Total - Fair Value	22,814
Total - Unrealized	(47)
US Treasury and Agencies
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	127,143
Unrealized Losses Less Than 12 Months - Unrealized	(166)
Total - Fair Value	127,143
Total - Unrealized	(166)
Government-Sponsored Enterprises
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	11,466
Unrealized Losses Less Than 12 Months - Unrealized	(17)
Total - Fair Value	11,466
Total - Unrealized	(17)
Foreign Government Bonds
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	16,906
Unrealized Losses Less Than 12 Months - Unrealized	(63)
Total - Fair Value	16,906
Total - Unrealized	(63)
Corporate Notes And Bonds
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	260,575
Unrealized Losses Less Than 12 Months - Unrealized	(643)
Unrealized Losses 12 Months or Greater - Fair Value	4,709
Unrealized Losses 12 Months or Greater - Unrealized	(31)
Total - Fair Value	265,284
Total - Unrealized	(674)
Mortgage Backed Securities - Residential
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	21,186
Unrealized Losses Less Than 12 Months - Unrealized	(296)
Unrealized Losses 12 Months or Greater - Fair Value	2,050
Unrealized Losses 12 Months or Greater - Unrealized	(25)
Total - Fair Value	23,236
Total - Unrealized	(321)
Mortgage Backed Securities - Commercial
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	66,447
Unrealized Losses Less Than 12 Months - Unrealized	(436)
Unrealized Losses 12 Months or Greater - Fair Value	5,756
Unrealized Losses 12 Months or Greater - Unrealized	(119)
Total - Fair Value	72,203
Total - Unrealized	$ (555)