Note 9 - Retirement Plans (Detail) - Components of net periodic benefit cost for pension plans (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Components of net periodic pension cost:
Service cost	$ 4,452	$ 3,447	$ 3,199
Interest cost	3,315	2,943	2,658
Expected return on plan assets	(2,609)	(2,351)	(1,987)
Recognized net actuarial loss	2,527	958	912
Net periodic pension cost	$ 7,685	$ 4,997	$ 4,782