Note 6 - Other Comprehensive Income (Details) - Line Items Impacted By Components Of Other Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Securities available for sale:
Realized gains on securities transactions	$ 2,157	$ 938	$ 745	$ (3,022)
Income taxes	960	417	332	(1,346)
Net of tax	1,197	521	413	(1,676)
Amortization of pension and post-retirement benefit items:
Amortization of net actuarial losses	1,580	1,017	2,603	1,833
Amortization of prior service cost		10	10	20
Income taxes	(703)	(456)	(1,163)	(824)
Net of tax	877	571	1,450	1,029
Total reclassifications, net of tax	759	388	1,259	358
Available For Sale [Member]
Securities available for sale:
Realized gains on securities transactions	(213)	(329)	(345)	(1,208)
Income taxes	95	146	154	537
Net of tax	(118)	(183)	(191)	(671)
Amortization of Pension and Post-retirement Benefit Items [Member]
Amortization of pension and post-retirement benefit items:
Amortization of net actuarial losses	1,580	1,017	2,603	1,833
Amortization of prior service cost	0	10	10	20
Income taxes	(703)	(456)	(1,163)	(824)
Net of tax	$ 877	$ 571	$ 1,450	$ 1,029