Note 11 - Shareholders' Equity (Tables)

12 Months Ended

Dec. 31, 2016

Notes Tables

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	Shares Under Option			Weighted Average Price		Weighted Average Remaining Contract Life (Years)		Aggregate Intrinsic Value (000’s)
Outstanding January 2, 2016		470,904		$	80.53
Granted		123,435			120.15
Exercised		(229,319	)		73.42
Forfeited		(8,836	)		87.86
Outstanding December 31, 2016		356,184			98.65		5.0	$	18,920
Exercisable December 31, 2016		112,714			78.16		3.6		8,297

Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]

	Shares			Weighted Average Grant-Date Fair Value
Nonvested January 2, 2016		194,461		$	89.32
Granted		115,121			117.79
Vested		(93,742	)		84.94
Forfeited		(8,543	)		93.85
Nonvested December 31, 2016		207,297			106.92

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	2016			2015			2014
Weighted average fair value of options granted	$	26.06		$	21.99		$	26.25
Assumptions:
Risk-free interest rate		1.37	%		1.25	%		1.67	%
Expected dividend yield		0.97	%		1.04	%		0.93	%
Expected stock price volatility		26.0	%		28.0	%		33.0	%
Expected life of options (years)		4.6			4.6			4.6

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

(in thousands)	Pension and postretirement liability and reclassification adjustments (a)			Gain on investments			Foreign currency translation adjustment			Accumulated other comprehensive income (loss)
Balance at December 27, 2014	$	(29,615	)	$	10,791		$	(2,302	)	$	(21,126	)
2015 activity		20,893			793			(46,231	)		(24,545	)
Balance at January 2, 2016		(8,722	)		11,584			(48,533	)		(45,671	)
2016 activity		(3,261	)		(815	)		(24,832	)		(28,908	)
Balance at December 31, 2016	$	(11,983	)	$	10,769		$	(73,365	)	$	(74,579	)