Note 6 - Other Assets and Other Liabilities (Details Textual) $ / shares in Units, shares in Thousands, $ in Thousands			3 Months Ended		9 Months Ended
	Sep. 28, 2023	Jun. 29, 2023	Sep. 30, 2023 USD ($) $ / shares shares	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) $ / shares shares	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Share Price (in dollars per share) | $ / shares			$ 230.01		$ 230.01
LIHTC Investments			$ 30,107		$ 30,107		$ 34,421
Qualified Affordable Housing Project Investments, Commitment			$ 16,138		$ 16,138		22,647
Lessee, Operating Lease, Term of Contract (Year)			5 years		5 years
Lessee, Operating Lease, Renewal Term (Year)			5 years		5 years
Operating Lease, Liability			$ 18,593		$ 18,593		15,746
Operating Lease, Right-of-Use Asset			$ 18,593		$ 18,593		$ 15,746
Operating Lease, Weighted Average Remaining Lease Term (Year)			3 years 7 months 6 days		3 years 7 months 6 days
Operating Lease, Weighted Average Discount Rate, Percent			2.78%		2.78%
Operating Lease, Cost			$ 1,633	$ 1,664	$ 4,949	$ 4,934
Contingent Commitment, Remainder of Fiscal Year [Member]
Qualified Affordable Housing Project Investments, Commitment			4,483		4,483
Contingent Commitment, Year 1 [Member]
Qualified Affordable Housing Project Investments, Commitment			10,499		10,499
Contingent Commitment, Year 2 [Member]
Qualified Affordable Housing Project Investments, Commitment			359		359
Contingent Commitment, Year 3 [Member]
Qualified Affordable Housing Project Investments, Commitment			59		59
Contingent Commitment, Year 4 [Member]
Qualified Affordable Housing Project Investments, Commitment			190		190
Contingent Commitment, Year 5 or Thereafter [Member]
Qualified Affordable Housing Project Investments, Commitment			$ 548		$ 548
VISA Class B Common Stock [Member]
Investment Owned, Balance, Shares (in shares) | shares			211		211
Conversion Rate of Class B Common Stock into Class A Common Stock	1.5875	1.5902
VISA Class B Common Stock [Member] | Reported Value Measurement [Member]
Investment Owned, at Fair Value			$ 0		$ 0