Investment Securities (Details 1) (USD $) In Thousands, unless otherwise specified	Apr. 01, 2012
Schedule of Amortized Cost and Estimated Fair Value of Debt Securities
Due in one year or less, Amortized Cost	$ 71,344
Due after one year through three years, Amortized Cost	205,258
Due after three years through five years, Amortized Cost	45,519
Due after five years, Amortized Cost	50,015
Total amortized cost of debt securities	372,136
Due in one year or less, Estimated Fair Value	71,702
Due after one year through three years, Estimated Fair Value	205,905
Due after three years through five years, Estimated Fair Value	45,618
Due after five years, Estimated Fair Value	50,214
Total estimated fair value of debt securities	$ 373,439

Available for sale securities debt maturities after five years amortized cost.

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