Schedule of Fixed Income Securities in Unrealized Loss Positions (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	$ 503,420
Unrealized Losses Less Than 12 Months - Unrealized	(1,686)
Unrealized Losses 12 Months or Greater - Fair Value	10,841
Unrealized Losses 12 Months or Greater - Unrealized	(173)
Total - Fair Value	514,261
Total - Unrealized	(1,859)
Municipal Notes And Bonds
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	17,114
Unrealized Losses Less Than 12 Months - Unrealized	(28)
Total - Fair Value	17,114
Total - Unrealized	(28)
US Treasury and Agencies
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	96,394
Unrealized Losses Less Than 12 Months - Unrealized	(166)
Total - Fair Value	96,394
Total - Unrealized	(166)
Government-Sponsored Enterprises
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	14,071
Unrealized Losses Less Than 12 Months - Unrealized	(30)
Total - Fair Value	14,071
Total - Unrealized	(30)
Foreign Government Bonds
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	18,487
Unrealized Losses Less Than 12 Months - Unrealized	(86)
Total - Fair Value	18,487
Total - Unrealized	(86)
Corporate Notes And Bonds
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	261,299
Unrealized Losses Less Than 12 Months - Unrealized	(729)
Unrealized Losses 12 Months or Greater - Fair Value	6,465
Unrealized Losses 12 Months or Greater - Unrealized	(20)
Total - Fair Value	267,764
Total - Unrealized	(749)
Mortgage Backed Securities - Residential
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	20,974
Unrealized Losses Less Than 12 Months - Unrealized	(243)
Unrealized Losses 12 Months or Greater - Fair Value	127
Unrealized Losses 12 Months or Greater - Unrealized	(9)
Total - Fair Value	21,101
Total - Unrealized	(252)
Mortgage Backed Securities - Commercial
Schedule of Available-for-sale Securities [Line Items]
Unrealized Losses Less Than 12 Months - Fair Value	75,081
Unrealized Losses Less Than 12 Months - Unrealized	(404)
Unrealized Losses 12 Months or Greater - Fair Value	4,249
Unrealized Losses 12 Months or Greater - Unrealized	(144)
Total - Fair Value	79,330
Total - Unrealized	$ (548)