Investments (Unrealized Losses and Fair Value by Length of Time) (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Mar. 30, 2019
Debt Securities in a Continuous Unrealized Loss Position
Less than 12 Months, Fair Value	$ 1,000	$ 1,662
Less than 12 month, Unrealized Losses	(2)	(17)
12 Months or Longer, Fair Value	3,248	8,895
12 Months or Longer, Unrealized Losses	(49)	(141)
Debt Securities, Available-for-sale, Unrealized Loss Position	4,248	10,557
Gross Unrealized Losses	(51)	(158)
Residential mortgage-backed securities
Debt Securities in a Continuous Unrealized Loss Position
Less than 12 Months, Fair Value	399	1,066
Less than 12 month, Unrealized Losses	0	(9)
12 Months or Longer, Fair Value	2,896	5,206
12 Months or Longer, Unrealized Losses	(48)	(110)
Debt Securities, Available-for-sale, Unrealized Loss Position	3,295	6,272
Gross Unrealized Losses	(48)	(119)
State and political subdivision debt securities
Debt Securities in a Continuous Unrealized Loss Position
Less than 12 Months, Fair Value	302	353
Less than 12 month, Unrealized Losses	(1)	0
12 Months or Longer, Fair Value	102	2,319
12 Months or Longer, Unrealized Losses	(1)	(17)
Debt Securities, Available-for-sale, Unrealized Loss Position	404	2,672
Gross Unrealized Losses	(2)	(17)
Corporate Debt Securities
Debt Securities in a Continuous Unrealized Loss Position
Less than 12 Months, Fair Value	299	243
Less than 12 month, Unrealized Losses	(1)	(8)
12 Months or Longer, Fair Value	250	1,073
12 Months or Longer, Unrealized Losses	0	(11)
Debt Securities, Available-for-sale, Unrealized Loss Position	549	1,316
Gross Unrealized Losses	$ (1)	(19)
U.S. Treasury and government debt securities
Debt Securities in a Continuous Unrealized Loss Position
Less than 12 Months, Fair Value		0
Less than 12 month, Unrealized Losses		0
12 Months or Longer, Fair Value		297
12 Months or Longer, Unrealized Losses		(3)
Debt Securities, Available-for-sale, Unrealized Loss Position		297
Gross Unrealized Losses		$ (3)