Note 18 - Fair Value Measurements (Details) - Fair Value of Financial Assets Measure on a Recurring Basis (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Available-for-sale securities:
Available-for-sale securities	$ 177,531	$ 191,342
Assets held in trading accounts	8,739	6,224
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities:
Available-for-sale securities	159,390	152,481
US Government Agencies Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities	159,390	152,481
Mortgage-backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities:
Available-for-sale securities	2,078	20,634
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Available-for-sale securities:
Available-for-sale securities	2,078	20,634
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities:
Available-for-sale securities	1,262	2,988
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities	1,262	2,988
Other Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities:
Other securities	1,504	1,504
Other Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities:
Other securities	13,297	13,735
Other Securities [Member]
Available-for-sale securities:
Available-for-sale securities	14,801	15,239
Other securities	14,801	15,239
Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities:
Assets held in trading accounts	1,750	1,800
Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities:
Assets held in trading accounts	$ 6,989	$ 4,424