Note 5 - Fair Value - Investment Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Jan. 01, 2017	Mar. 27, 2016
Assets:
Investment assets	$ 190,735	$ 47
US Government Corporations and Agencies Securities [Member]
Assets:
Investment assets	21,161
Corporate Debt Securities [Member]
Assets:
Investment assets	96,993
US States and Political Subdivisions Debt Securities [Member]
Assets:
Investment assets	4,195
Fair Value, Inputs, Level 1 [Member]
Assets:
Investment assets	76,155	4
Fair Value, Inputs, Level 1 [Member] | US Government Corporations and Agencies Securities [Member]
Assets:
Investment assets	11,041
Fair Value, Inputs, Level 1 [Member] | Corporate Debt Securities [Member]
Assets:
Investment assets
Fair Value, Inputs, Level 1 [Member] | US States and Political Subdivisions Debt Securities [Member]
Assets:
Investment assets
Fair Value, Inputs, Level 2 [Member]
Assets:
Investment assets	114,580	43
Fair Value, Inputs, Level 2 [Member] | US Government Corporations and Agencies Securities [Member]
Assets:
Investment assets	10,120
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member]
Assets:
Investment assets	96,993
Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member]
Assets:
Investment assets	4,195
Money Market Funds [Member]
Assets:
Investment assets	65,114	4
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Investment assets	65,114	4
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Investment assets
CounterPath [Member]
Assets:
Investment assets		43
CounterPath [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Investment assets
CounterPath [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Investment assets		$ 43
Certificates of Deposit [Member]
Assets:
Investment assets	3,272
Certificates of Deposit [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Investment assets
Certificates of Deposit [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Investment assets	$ 3,272