Note 14 - Additional Cash Flow Information (Details) - Additional Cash Flow Information - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Note 14 - Additional Cash Flow Information (Details) - Additional Cash Flow Information [Line Items]
Interest paid	$ 21,700	$ 14,274	$ 11,908
Income taxes paid	20,127	18,832	14,867
Transfers of Loans Not Covered by FDIC Loss Share to Foreclosed Assets Held-for-sale [Member]
Note 14 - Additional Cash Flow Information (Details) - Additional Cash Flow Information [Line Items]
Transfers of acquired balances transferred to other accounts	16,456	5,145	7,358
Transfers of Loans Acquired Covered by FDIC Loss Share to Foreclosed Assets Covered by FDIC Loss Share [Member]
Note 14 - Additional Cash Flow Information (Details) - Additional Cash Flow Information [Line Items]
Transfers of acquired balances transferred to other accounts	4,349	5,536	9,239
Transfers of Foreclosed Assets Covered by FDIC Loss Share to Foreclosed Assets Held for Sale [Member]
Note 14 - Additional Cash Flow Information (Details) - Additional Cash Flow Information [Line Items]
Transfers of acquired balances transferred to other accounts	13,895	0	0
Transfers of Loans Acquired Covered by FDIC Loss Share, to Loans Acquired not Covered by FDIC Loss Share [Member]
Note 14 - Additional Cash Flow Information (Details) - Additional Cash Flow Information [Line Items]
Transfers of acquired balances transferred to other accounts	88,922	0	0
Transfers of Premises Held-for-sale to Foreclosed Assets Held-for-sale [Member]
Note 14 - Additional Cash Flow Information (Details) - Additional Cash Flow Information [Line Items]
Transfers of acquired balances transferred to other accounts	$ 6,126	$ 0	$ 0