Note 7 - Employee Benefit Plans (Detail) - Net Periodic Pension Cost (Income) (Pension Benefits [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Pension Benefits [Member]
Service cost	$ 1,057	$ 993
Interest cost	970	1,017
Expected return on plan assets	(1,204)	(1,145)
Amortization of prior service cost	97	100
Amortization of net loss	776	707
Net periodic benefit cost	$ 1,696	$ 1,672